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INSECT    PESTS 

OF 

FARM,  GARDEN  AND 
ORCHARD 

BY 

E.  DWIGHT  SANDERSON 

Formerly  Entomologist  of  the  Delavuare,  Texas  and  New  Hampshire  AgritulturaJ 

Experiment  Stations  and  Director  of  the  New  Hampshire  and 

West  Virginia  Agricultural  Experiment  Stations. 


SECOND  EDITION 
REVISED  AND   ENLARGED 

BY 

LEONARD  MARION  PEAIRS 

Professor  of  Entomology  West  Virginia  University 


NEW  YORK 

JOHN  WILEY  AND  SONS,  Inc. 

London:   CHAPMAN  &   HALL,    Limited. 
1921 


COPYRIGHT,   1912 
BY 

E.  DWIGHT  SANDERSON 


COPYRIGHT,    1921 
BY 

E.  DWIGHT  SANDERSON 

AMD 

LEONARD  M.  PEAIRS 


Printed  in  ihe  U.  S.  A. 


PREFACE 


The  edition  of  the  writer's  "Insects  Injurious  to  Staple 
Crops,"  first  published  ten  years  ago,  having  been  exhausted,  the 
publishers  requested  a  revision.  It  was  found,  however,  that  the 
advances  in  economic  entomology  during  the  past  decade  were  such 
that  it  was  necessary  practically  to  rewrite  the  book.  At  the 
time  it  was  first  pubUshed  two  other  books  were  projected;  one 
to  deal  with  the  insects  affecting  garden  crops,  and  the  other  to 
discuss  those  affecting  fruits.  Pressure  of  regular  work  pre- 
vented the  author  from  completing  the  manuscript  for  these 
works  and  in  1907  Dr.  Chittenden  issued  his  excellent  book  on 
"  Insects  Injurious  to  Vegetables,"  so  that  there  seemed  to  be 
no  immediate  demand  for  another  volume  on  that  subject.  At 
the  same  time  two  other  well-known  entomologists  were  work- 
ing upon  books  which  would  cover  fruit  insects,  so  that  the 
writer  abandoned  the  field  to  them.  Subsequently,  the  work 
of  one  of  these  friends  was  cut  short  by  his  sudden  death,  and 
the  other  abandoned  the  task,  at  least  for  the  present. 

Under  these  circumstances,  it  seemed  that  there  was  a  distinct 
place  for  a  book  to  cover  all  the  insects  affecting  the  crops  of 
farm,  garden  and  orchard,  and  having  leisure  to  devote  to  it,  the 
author  developed  the  work  in  its  present  form. 

It  has  been  the  author's  effort  to  discuss  all  of  the  more  impor- 
tant insects  of  farm,  and  garden  and  orchard  at  sufficient  length 
to  give  a  clear  idea  of  their  Kfe  histories  and  habits,  and  also  the 
best  means  of  control,  so  that  the  book  may  be  used  as  a  reference 
work  both  by  the  student  of  economic  entomology  and  by 
the  practical  farmer,  gardener,  or  fruit-grower.  Insects  of  minor 
or  local  importance  have  been  purposely  omitted.  The  insects 
of  practically  all  of  the  leading  crops  are  considered,  except  the 
citrus  fruits.  With  these  the  author  is  unfamihar,  but  it  is 
hoped  to  add  a  chapter  upon  them  by  a  competent  authority 
in  a  subsequent  edition.     In  general,  the  discussion  of  insects 


ii  PREFACE 

and  their  control  as  given  is  based  upon  conditions  east  of  the 
Rockies,  and  practically  no  consideration  has  been  given  to  the 
conditions  of  the  Pacific  Coast  or  of  the  irrigated  country  of  the 
far  West. 

The  author  is  well  aware  that  there  are  doubtless  many  errors 
of  fact  or  of  wrong  emphasis  in  these  pages.  Such  must  nec- 
essarily be  the  case  in  a  work  the  greater  part  of  which  must  be 
compiled.  All  of  the  leading  authorities  on  the  subject  discussed 
have  been  consulted  and  the  writer  has  endeavored  to  present 
their  evidence  fairly,  with  such  interpretation  as  his  personal 
knowledge  made  possible.  He  will  be  greatly  indebted  to  those 
who  will  aid  him  in  securing  the  accuracy  of  the  work  by  report- 
ing any  errors  or  by  suggesting  improvements  in  it,  as  it  is  hoped 
to  revise  the  pages  from  time  to  time  so  that  they  may  serve 
as  a  reliable  reference  work  upon  our  insect  pests  of  the  farm, 
the  garden,  and  the  orchard. 

On  the  following  pages  are  given  the  sources  from  which 
the  illustrations  have  been  secured,  but  the  author  wishes  to 
express  his  special  appreciation  of  the  very  large  number  of  figures 
which  were  furnished  him  by  Dr.  L.  0.  Howard,  Chief  of  the 
Bureau  of  Entomology,  and  Mr.  J.  A.  Arnold,  Chief  of  the 
Division  of  Publications,  of  the  United  States  Department  of 
Agriculture,  either  as  electrotypes  or  original  drawings  or  photo- 
graphs, and  to  Ginn  &  Company  of  Boston,  for  the  loan  of 
numerous  electrotypes  made  for  an  Elementary  Entomology  by 
Prof.  C.  F.  Jackson  and  the  writer,  now  being  pubhshed  by 
them. 

E.  DwiGHT  Sanderson. 

West  Virginia  University, 
morqantown. 


PREFACE  TO  THE  SECOND  EDITION. 


No  better  indication  of  the  activity  of  the  students  of  American 
economic  entomology  could  be  cited  than  the  fact  that  a  text 
book  dealing  with  injurious  insects  requires  revision  at  rather 
frequent  intervals.  The  present  revision  is  issued  in  the  hope 
that  it  may  record  in  some  measure  the  progress  which  investi- 
gators have  made  since  the  book  was  first  prepared. 

Since  the  publication  of  the  first  edition  the  senior  author 
has  left  active  work  in  economic  entomology,  but  he  has  been 
fortunate  in  securing  the  collaboration  of  his  former  colleague, 
who  has  made  a  thorough  revision  of  the  original  text.  He  has 
added  several  new  articles  and  three  new  chapters  deaUng  with 
the  insect  pests  directly  affecting  man  and  the  domestic  animals 
and  with  the  insects  affecting  citrus  fruits. 

Other  changes  in  the  text  will  be  found  to  be  minor  ones, 
with  the  exception  of  the  additions  mentioned,  and  are  mainly 
for  the  purpose  of  bringing  up  to  date  the  recommendations  for 
control. 

No  attempt  to  conform  to  the  latest  usage  in  naming  of 
families  has  been  made  for  the  reason  that  most  students  using 
this  text  will  be  more  familiar  with  the  names  as  used  in  Com- 
stock's  Manual  than  with  the  modern  usage. 

May,  1920.  E.  Dwight  Sanderson. 


ui 


ACKNOWLEDGEMENTS 


The  authors  wish  to  express  their  sincere  appreciation  of  the 
courtesy  extended -by  those  friends  mentioned  below  who  have 
assisted  in  this  work  by  furnishing  electrotypes,  photographs  and 
drawings,  thus  making  possible  the  illustration  of  the  volume. 

The  United  States  Department  of  Agriculture,  through  Dr. 
L.  O.  Howard,  Chief  of  the  Bureau  of  Entomology,  and  Mr. 
J.  A.  A.  Arnold,  Chief  of  the  Division  of  Publications,  furnished 
a  large  number  of  electrotypes  and  plates.  The  illustrations  cred- 
ited to  Dr.  C.  V.  Riley  have  been  secured  from  various  sources. 

Dr.  S.  A.  Forbes,  State  Entomologist  of  IlHnois,  Prof.  Glen 
W.  Herrick  of  Cornell  University,  Prof.  F.  L.  Washburn  of  Min- 
nesota, Prof.  H.  A.  Gossard  of  the  Ohio  Station,  Prof.  R.  H. 
Petit  of  Michigan  Agr.  College,  Prof.  P.  J.  Parrott  of  the  New 
York  Station  at  Geneva,  and  the  late  Dr.  John  B.  Smith  of 
New  Jersey,  all  furnished  several  illustrations.  Prof.  W.  E. 
Rumsey  of  West  Virginia  made  his  excellent  collection  of  photo- 
graphs available. 

Prof.  H.  Garman  of  Kentucky,  Director  R.  W.  Thatcher  of 
the  Washington  Expt.  Station,  Prof.  S.  J.  Hunter  of  the  University 
of  Kansas,  Prof.  T.  B.  Symons  of  Maryland,  Prof.  H.  E.  Summers 
of  Iowa,  Director  P.  H.  Rolfs  of  the  Florida  Station,  Dr.  T.  C. 
Johnson  of  the  Virginia  Truck  Station,  Director  J.  C.  Kendall  of 
the  New  Hampshire  Station,  Director  S.  W.  Fletcher  of  the  Vir- 
ginia Station,  Dr.  W.  E.  Britton  of  Connecticut,  Prof.  R.  I.  Smith 
of  North  Carolina,  Dr.  A.  L.  Quaintance  of  the  Bureau  of  Ento- 
mology, Director  F.  B.  Mumford  of  the  Missouri  Station,  and 
Prof.  C.  S.  Crandall  of  the  Illinois  Station,  all  furnished  several 
valuable  illustrations. 

Dr.  E.  W.  Berger  kindly  read  over  the  copy  for  the  chapter 
on  Citrus  Fruit  Insects  and  assisted  by  correcting  mistaken 
statements  and  offering  many  helpful  suggestions  for  the  im- 
provement of  the  chapter. 

iv 


ACKNOWLEDGEMENTS  v 

The  Friend  Mfg.  Co.,  The  Deming  Co.,  F.  E.  Myers  and 
Bro.,  The  Spraymotor  Co.,  E.  C.  Brown  and  Co.,  The  Goulds 
Mfg.  Co.,  and  the  Bean  Spray  Pump  Co.,  all  makers  of  spraying 
appliances,  furnished  many  of  the  illustrations  of  such  apparatus, 
while  the  Corona  Chemical  Co.  and  the  Niagara  Sprayer  Co. 
furnished  some  of  the  illustrations  of  dusters. 

The  Orange  Judd  Publishing  Co.  furnished  some  of  the  Riley 
figures. 

Many  others  helped  by  allowing  their  illustrations  to  be  used. 

All  illustrations  have  been  properly  credited  in  the  text. 
Credit  for  much  of  the  direct  and  indirect  assistance  freely  given 
by  many  persons  can  not  be  extended  to  individuals  but  is  none 
the  less  appreciated. 

The  pubhshers  of  this  volume,  John  Wiley  and  Sons,  Inc., 
have  done  all  in  their  power  to  cooperate  with  the  authors  and 
make  the  task  of  preparing  the  manuscript  as  light  as  possible, 
and  to  them  and  their  organization  we  wish  to  extend  our  thanks. 


CONTENTS 


Preface  to  the  First  Edition i 

Preface  to  the  Revised  Edition iii 

Acknowledgments iv 

Chapter  page 

I.  Injury  to  Crops  by  Insect  Pests 1 

II.  Beneficial  Insects,  Predaceous  and  Parasitic 8 

III.  Structure  and  Development  of  Insects 20 

IV.  Farm  Methods  for  the  Control  of  Insects 29 

V.  Insecticides 39 

VI.  Spraying  and  Dusting  Apparatus 59 

VII.  Insects  Affecting  Grains,  Grasses  and  Miscellaneous 

Crops 78 

VIII.  Insects  Injurious  to  Small  Grains 117 

IX.  Insects  Injurious  to  Corn 143 

X.  Insects  Injurious  to  Stored  Grains 176 

XI.  Insects  Injurious  to  Clover  and  Alfalfa 189 

XII.  Insects  Injurious  to  Tobacco 212 

XIII.  Insects  Injurious  to  Cotton 226 

XIV.  Insects  Injurious  to  Potatoes  and  Tomatoes 256 

XV.  Insects  Injurious  to  Beans  and  Peas .* 278 

XVI.  Insects  Injurious  to  Beets  and  Spinach 299 

XVII.  Insects  Injurious  to  Cabbage  and  Related  Crops 314 

XVIII.  Insects  Injurious  to  Melons,  Cucumbers,  Squash,    Etc  . .  340 

XIX.  Insects  Injurious  to  Miscellaneous  Garden  Crops 361 

XX.  Insects  Injurious  to  the  Strawberry 389 

XXI.  Insects  Injurious  to  the  Raspberry  and  Blackberry  ....  403 
XXII.  Insects  Injurious  to  the  Currant  and  Gooseberry 418 

XXIII.  Insects  Injurious  to  the  Grape 432 

XXIV.  Insects  Injurious  to  Orchard  Fruits 470 

XXV.  Insects  Injurious  to  the  Apple  and  Pear 514 

XXVI.  Insects  Injurious  to  the  Peach,  Plum  and  Cherry 575 

XXVII.  Insects  Injurious  to  Citrus  Fruits 599 

XXVIII.  Insects  Injurious  to  Man  and  in  the  Household 635 

XXIX.  Insects  Injurious  to  Domestic  Animals  and  Poultry  ....  657 

Bibliography 689 

Index 692 

vi 


INSECT  PESTS 

OF 

FARM,  GARDEN  AND  ORCHARD 


CHAPTER  I 

THE  INJURY  TO  CROPS  BY  INSECT  PESTS 

Ever  since  the  locust  plagues  in  the  time  of  the  Pharaohs  his- 
tory is  replete  with  accounts  of  insect  scourges  and  the  enormous 
losses  they  have  caused  the  agriculturists  of  all  ages.  However, 
instead  of  diminishing  with  the  advancement  of  agricultural 
methods,  injurious  insects  have  undoubtedly  become  both  more 
numerous  and  more  destructive  in  modern  times.  "  In  no  coun- 
try in  the  world  do  insects  impose  a  heavier  tax  on  farm  products 
than  in  the  United  States.  The  losses  resulting  from  the  depre- 
dations of  insects  on  all  the  plant  products  of  the  soil,  both  in 
their  growing  and  in  their  stored  state,  together  with  those  on 
live  stock,  exceed  the  entire  expenditures  of  the  National  Gov- 
ernment, including  the  pension  roll  and  the  maintenance  of  the 
Aimy  and  the  Navy."*  ''  Very  careful  estimates,  based  on  crop 
reports  and  actual  insect  damage  over  a  series  of  years,  show 
that  the  loss  due  to  insect  pests  of  farm  products,  including 
fruits  and  live  stock,  now  reaches  the  almost  inconceivable  total 
of  SI, 000,000,000,  annually." t  The  above  quotations  from  Mr. 
C.  L.  Marlatt,  Assistant  Chief  of  the  Bureau  of  Entomology, 
United  States  Department  of  Agriculture,  may  appear  to  the  reader 
either  ludicrous  or  startling,  according  to  the  extent  of  his  infor- 
mation concerning  the  role  which  insects  play  in  our  Agricultural 

*  C.  L.  Marlatt,  Yearbook  U.  S.  Department  of  Agriculture,  1904,  p.  461. 
f  C.  L.  Marlatt,  Journal  of  Economic  Entomology,  IV,  109. 


2  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

economy,  which  forms  the  warp  of  American  prosperity.  It 
should  be  borne  in  mind  that  these  figures  are  based  on  pre-war 
estimates  and  that  they  now  need  considerable  revision  upward 
but  that  the  totals  will  not  reach  the  amounts  expended  by 
the  nation  during  a  state  of  war, 

A  brief  resume  of  the  damage  done  by  insect  pests,  of  the 
costs  of  fighting  them  and  of  the  estimates  which  form  the  basis 
for  the  above  statements  will  make  them  more  convincing. 

Growing  Cereals. — Probably  no  insect  does  as  widespread 
damage  as  the  Hessian-fly,  attacking  our  chief  staple,  wheat,  as 
well  as  rye  and  barley.  One-tenth  of  the  whole  crop,  valued  at 
$150,000,000  to  $175,000,000  is  generally  conceded  to  be  destroyed 
by  this  pest  every  year.  In  some  sections  the  loss  is  frequently 
as  great  as  30  to  50  per  cent,  and  it  undoubtedly  was  responsible 
in  a  great  measure  for  the  necessity  for  governmental  regulations 
of  the  use  of  wheat  flour  during  the  great  war.  The  southern 
grain-louse  or  "  green-bug "  caused  a  loss  estimated  at  from 
$5,000,000  to  $10,000,000  in  Texas,  Oklahoma  and  Kansas  in 
1907,  and  every  year  there  is  a  considerable  shrinkage  in  the  wheat 
crop  as  a  result  of  the  presence  of  this  and  other  species  of  plant- 
lice.  This  injury  will  doubtless  amount,  on  the  average,  to  as 
much  as  2  or  3  per  cent  of  the  entire  crop,  worth  from  $30,000,000 
to  $50,000,000. 

The  corn  crop  of  1919  was  worth  at  least  three  and  one-half 
billions  of  dollars.  The  total  was  reduced  at  least  two  to  three 
per  cent  by  the  chinch-bug  and  not  less  than  5  per  cent  by  the 
corn-earworm  while  other  insects  accounted  for  several  per  cent 
more  or  less.  Estimating  the  total  insect  depreciation  of  this 
crop  at  only  ten  per  cent  gives  a  total  of  $350,000,000  for  the  one 
year. 

The  total  value  of  cereal  crops  in  1919  was  over$7,000,000,000, 
which  was  undoubtedly  at  least  ten  per  cent  less  than  it  would 
have  been  could  the  insect  injury  have  been  totally  eliminated. 

Hay  and  Forage  Crops. — A  host  of  small  insects  attack  our 
grasses  and  forage  crops,  many  of  them  being  so  small  that  they 
are  unnoticed,  though  their  aggregate  injury  is  sometimes 
enormous.  Of  the  larger  pests  of  grasses  and  forage  plants  the 
army  worms  are  among  the  best  known  and  have  often  caused  a, 
loss  of  over  half  a  million  dollars  to  a  single  state  in  one  season. 


INJURY  TO  CROPS  BY  INSECT  PESTS  3 

Grasshoppers  of  various  species  are  also  always  more  or  less 
injurious  and  often  become  a  serious  menace.  Probably  the  most 
serious  injury,  however,  is  done  by  subterranean  larva?  such  as 
the  cut-worms,  wireworms,  white  grubs,  and  webworms,  which 
breed  in  sod  land,  and  by  the  hordes  of  little  leaf -hoppers  which 
are  always  prevalent,  but  whose  injury  often  passes  unnoticed. 
Ten  per  cent  of  the  hay  crop  was  worth  $150,000,000  in  1919  and 
this  is  a  fair  estimate  of  the  damage  done  to  hay  and  forage  crops 
by  their  insect  enemies. 

Cotton. — The  cotton  plant  has  a  number  of  injurious  insect 
enemies,  of  which  the  boll  weevil,  bollworm,  and  leafworm  are 
the  most  injurious.  In  1904  the  writer  made  a  statistical  study 
of  the  decrease  in  the  cotton  crop  of  Texas  due  to  the  boll 
weevil,  and  showed  that  it  was  then  costing  that  state  $25,000,000 
per  annum.*  This  estimate  has  been  confirmed  by  independent 
investigations  made  by  Mr.  W.  D.  Hunter  of  the  U.  S.  Bureau 
of  Entomology,  and  although  the  loss  in  Texas  is  not  so  serious 
at  present,  the  weevil  has  spread  eastward  as  far  as  Georgia,  so 
that  its  total  injury  remains  practically  the  same,  and  has 
undoubtedly  been  a  large  factor  in  the  higher  price  of  cotton 
in  recent  years.  The  bollworm  is  most  injurious  in  the  south- 
western cotton-producing  States,  where  it  causes  a  loss  from 
5  to  60  per  cent  of  the  crop.  The  total  damage  to  cotton  by 
the  bollworm  is  approximately  $100,000,000  per  annum  and  not 
infrequently  exceeds  that  amount.  In  1880  the  United  States 
Entomological  Commission  made  an  investigation  of  the  cotton 
worm  and  valued  its  ravages  at  $30,000,000,  but  with  the 
extensive  use  of  Paris  green  and  arsenical  poisons  its  injury  has 
been  greatly  reduced  and  now  amounts  to  from  $5,000,000  to 
$20,000,000  annually.  Various  minor  pests  of  the  cotton  plant 
inflict  a  considerable  amount  of  local  injury  and  with  the  above 
pests  damage  the  crop  at  least  10  per  cent,  worth  $160,000,000 
in  1919. 

Tobacco. — Tobacco  is  attacked  by  insects,  which  form  one 
of  the  chief  "  bugbears  "  of  tobacco  growing,  at  all  stages  of  its 
existence.  Ten  per  cent  of  the  crop,  worth  $35,000,000,  is  cer- 
tainly destroyed  by  them  every  year. 

*  E.  D.  Sanderson,  The  Boll  Weevil  and  the  Cotton  Crop  of  Texas.  (Bul- 
letin Dept.  of  Agriculture,  Insurance,  Statistics  and  History,  Austin,  Texas, 
1905,  p.  28,  7  maps.) 


4  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Truck  Crops. — Truck  crops  are  peculiarly  susceptible  to 
insect  attacks,  and  their  control  forms  one  of  the  chief  items  in 
the  cost  of  production.  It  is  safe  to  say  that  truck  crops  suffer 
from  insect  ravages  fully  twice  as  much  as  do  the  staples,  or  20 
per  cent  of  their  total  value.  Statistics  are  not  available  for 
the  present  value  of  truck  crops,  but  they  were  probably  worth 
$1,500,000,000  in  1919,  making  the  insect  tax  for  the  trucker 
fully  $300,000,000. 

Fruits. — Fruit  trees  are  also  much  more  seriously  injured 
by  insects  than  are  the  staple  crops,  and  their  control  involves 
a  large  expense  to  the  fruit-grower.  Where  it  is  not  combated, 
the  codling  moth,  or  apple  worm,  causes  a  loss  of  from 
30  to  50  per  cent  of  the  crop,  and  where  it  is  controlled  by 
spraying  a  considerable  expense  is  involved.  The  loss  and  cost 
of  treatment  for  this  pest  alone  amount,  to  $35,000,000  for  the 
United  States,  and  were  it  not  for  the  fact  that  it  is  now  largely 
controlled  in  the  principal  fruit-growing  sections,  the  loss  would 
be  double  or  treble  this  sum.  The  loss  due  to  the  San  Jose  scale 
is  difficult  to  estimate,  but  it  is  well  known  that  it  has  destroyed 
milHons  of  trees  and  that  in  the  principal  fruit  regions  whei'e  this 
pest  is  prevalent  it  is  necessary  to  treat  the  trees  annually 
at  a  cost  of  from  10  to  25  cents  per  tree,  so  that  $10,000,000  a 
year  would  be  a  very  conservative  estimate  of  its  annual  cost. 
Both  deciduous  and  citrus  fruits  have  a  host  of  insect  pests, 
always  present  and  doing  more  or  less  damage  and  occasionally 
becoming  so  abundant  as  to  threaten  the  life  of  the  trees  or  their 
crops.  Fifteen  per  cent  of  the  value  of  our  fruit  products, 
worth  at  least  $75,000,000,  is  certainly  destroyed  by  insect 
pests  every  year. 

Forest  Insects. — Only  those  who  have  had  opportunity  to 
observe  the  ravages  of  insects  in  timber  and  in  timber  products 
can  appreciate  the  enormous  losses  which  they  occasion.  Prob- 
ably no  one  is  better  informed  upon  this  matter  than  Dr.  A.  D. 
Hopkins,  in  charge  of  the  Forest  Insect  Investigations  of  the 
U.  S.  Bureau  of  Entomology,  who  has  made  a  life  study  of  these 
pests  in  all  parts  of  the  country.  In  a  recent  circular*  he  states 
that  "  the  amount  of  insect-killed  and  damaged  timber  left  in  the 
woods,  plus  the  reduction  in  value  of  that  utiHzed,  to  be  charged 

*A.  D.  Hopkins,  Circular  129,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


INJURY  TO  CROPS  BY  INSECT  PESTS  5 

to  insects  is  not  far  from  an  equivalent  of  10  per  cent  of  the  value 
of  the  annual  output  of  forest  products  of  all  kinds,  in  the  rough. 
The  total  value  of  the  forest  products  of  the  United  States  in  1907 
is  given  as  $1,280,000,000;  the  losses  from  insect  depredations 
would  therefore  represent  an  annual  loss  in  cash  value  of  more 
than  S 1 00 ,  000 ,  000 . "  To  this  should  be  added  a  similar  loss  to  farm 
woodlots,  which  may  be  estimated  at  an  additional  $10,000,000. 
The  insect  injury  to  the  shade  trees  of  city  streets,  parks, 
and  estates  should  also  be  mentioned,  for  such  pests  as  the  gypsy 
moth,  the  elm  leaf-beetle,  tussock  moths,  etc.,  are  not  only  causing 
enormous  losses  and  large  expense  for  their  control,  but  they  are 
often  reducing  the  values  of  real  estate  and  through  kilUng  the 
trees  are  destroying  the  scenic  value  of  property  and  changing  the 
esthetic  environment  in  a  manner  which  it  will  require  many 
decades  to  remedy,  if  the  previous  conditions  can  ever  be  even 
partially  reproduced.  The  State  Forester  of  Massachusetts  has 
recently  shown  that  the  New  England  States  and  the  Federal 
Government  have  spent  fully  $7,000,000  in  fighting  the  gypsy  and 
brown-tail  moths  in  New  England,  and  at  the  present  time  the 
New  England  States,  the  Federal  Government,  municipalities  and 
private  individuals  are  spending  over  $1,000,000  per  annum 
in  this  warfare  for  the  preservation  of  their  shade  and  forest 
trees. 

Live  Stock. — Insect  pests,  including  the  ticks  and  mites,  are 
almost  as  important  as  enemies  of  Hve  stock  as  of  crops.  The 
principal  drawback  to  cattle  raising  in  the  South  is  the  Texas 
fever,  transmitted  by  the  cattle  tick,  which  has  been  charged  by 
the  officials  of  the  bureau  of  Animal  Industry  with  a  loss  of 
$100,000,000  annually.  The  ox-warble,  which  causes  the  "grubby" 
hides  of  cattle,  causes  a  loss  estimated  at  from  $30,000,000  to 
$50,000,000  per  year  due  to  the  depreciated  value  of  the  hides  and 
the  lessened  quantity  and  poorer  quality  of  the  beef  of  affected 
animals.  The  screw-worm  fly  is  a  constant  annoyance  to  cattle  and 
source  of  loss  on  the  range,  and  numerous  biting  and  parasitic  flies 
cause  a  considerable  loss  to  the  grower  of  live  stock,  both  through 
actual  damage  and  through  the  annoyance  preventing  growth  and 
production.  The  sheep  scab,  sheep  tick,  the  sheep  bot  —  causing 
"  staggers  "  or  "  grub-in-the-head  " — -horn-fly,  buffalo-fly,  black- 
fly,  and  numerous  species  of  lice  which  affect  all  of  the  domestic 
animals,  are  among  the  pests  which  must  be  combated  by  the 


6  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

stockman.  In  1919  the  live  stock  products  were  worth 
$8,000,000,000,  and  it  is  estimated  that  fully  10  per  cent  of  this 
amount  was  lost  through  injury  from  insects. 

Stored  Products. — Even  after  the  crops  have  been  gathered 
and  garnered,  and  indeed  after  they  and  animal  products  have 
been  manufactured,  they  are  constantly  subject  to  the  attacks  of 
numerous  "  weevils,"  "  moths,"  and  other  insect  pests  of  stored 
products.  Every  housewife  and  every  merchant  knows  that  only 
through  constant  surveillance  these  ravages  can  be  prevented. 
Mills,  tobacco  warehouses,  storage  houses,  and  vessels,  must  be 
frequently  cleaned  and  often  must  be  fumigated  to  prevent  the 
increase  of  insect  pests  peculiar  to  them.  It  is  estimated  that  at 
least  3  per  cent  of  the  cereal  crops  are  destroyed  by  insects  while 
in  storage,  which  would  mean  a  loss  of  $200,000,000,  and  in  many 
cases  the  loss  to  corn,  particularly  in  the  South,  is  much  greater. 
The  total  loss  due  to  insects  in  stored  goods  of  all  kinds  is  impos- 
sible to  estimate,  but  would  fall  not  far  short  of  $300,000,000. 
With  this  brief  statement  of  the  losses  due  to  insect  pests  we 
may  summarize  them  in  a  table  which  will  show  that  the  total 
is  based  upon  conservative  estimates. 

Annual  Values  of  Farm  Crops  and  Losses  Chargeable  to 
Insect  Pests*. 


PRODUCT 


VALUE 


PERCENTAGE 
OF  LOSS 


AMOUNT  OF 
LOSS 


Cereals 

Hay  and  Forage .... 

Cotton 

Tobacco 

Truck  Crops 

Sugars 

Fruits 

Farm  Forests 

Miscellaneous  Crops. 
Animal  Products. . .  . 


{7,000,000,000 

1,500,000,000 

1,600,000,000 

375,000,000 

1,500,000,000 

200,000,000 

500,000,000 

110,000,000 

250,000,000 

8,000,000,000 


Total $21,035,000,000 


Natural  Forests  and  Forest  Products. 
Products  in  Storage 


Grand  Total . 


10 
10 
10 
10 
20 
10 
15 
10 
5 
5 


$700,000,000 

150,000,000 

160,000,000 

37,500,000 

300,000,000 

20,000,000 

75,000,000 

11,000,000 

12,500,000 

400,000,000 


$1,866,000,000 

100,000,000 
300,000,000 


$2,266,000,000 


♦Based  on  estimates  from  the  U.  S.  Bureau  of  Entomology  with  modifications  by  the 
writers.  Crop  values  based  on  estimates  from  the  U.  S.  Department  of  Agriculture  Year- 
book for  1918  and  various  estimates  for  the  year  1919. 


INJURY  TO  CROPS  BY  INSECT  PESTS  7 

This  table  will  indicate  that  two  billions  of  dollars  is  a  con- 
servative estimate  of  the  damage  done  by  insects  annually  to 
the  agricultural  interests  of  the  country. 

The  old  saying,  "  One  man's  loss  is  another  man's  gain  "  will 
not  apply  to  this  damage.  While  the  fluctuation  in  the  amount 
of  crops  does  influence  prices  received  by  the  farmers  it  does  not 
obviate  the  loss,  even  though  the  farmer  receives  as  much  money 
for  the  reduced  crop  as  he  would  have  for  a  full  crop.  The 
effect  is  merely  to  shift  the  burden  of  the  loss  from  the  farmer 
to  the  consumer.  The  damage  done  by  the  insects  remains  as  a 
definite  destruction  of  wealth  of  the  community  just  as  truly  as 
loss  from  fire  and  storm,  even  though  such  loss  is  borne  not  by 
the  owner  of  the  property  destroyed  but  by  an  insurance  company. 

A  real  benefit  to  the  community  at  large  from  these  insects 
is  coming  to  be  recognized  more  and  more.  That  is,  that  to 
succeed  against  the  handicaps  of  insect  injury  as  well  as  the  other 
hazards  incident  to  modern  agriculture,  the  farmer  must  be- 
come a  student  of  the  factors  insuring  success.  He  must,  as  he 
usually  can,  learn  the  methods  of  agriculture  best  suited  to  pre- 
vent the  loss  from  insects.  This  will  tend  to  broaden  his  educa- 
tion, to  make  him  more  observant  of  conditions  affecting  suc- 
cessful farming  and  indirectly  is  bound  to  make  him  a  more 
intelligent  and  efficient  farmer  and  a  better  citizen.  Who  can 
say  that  such  benefit  does  not  largely  overbalance  the  tremendous 
loss  due  to  the  presence  of  the  insects. 


CHAPTER  II 

BENEFICIAL  INSECTS,  PREDACEOUS  AND  PARASITIC 
Ladybird-beetles 

After  his  strawberries  have  been  ruined  by  the  strawberry 
weevil,  the  garden  truck  by  cutworms,  the  wheat  despoiled  by  the 
Hessian  fly,  the  melon-patch  fallen  a  prey  to  plant-hce,  and  the 
fruit  crop  has  been  a  failure  on  account  of  the  codhng  moth,  plum 
curcuho,  and  San  Jose  scale,  it  is  scarcely  surprising  that  the 
farmer  does  as  one  of  my  acquaintances  did  and  "  orders  the  hands 
to  kill  everything  that  crawls." 

But  such  would  be  entirely  too  heroic  a  measure,  and  if  strictly 
adhered  to  the  remedy  would  be  as  bad  as  the  disease,  for  it  would 
mean  not  only  useless  labor,  but  the  destruction  of  the  most  effect- 
ive means  whereby  insect  pests  are  held  in  check.  We  pride 
ourselves  • —  and  justly  —  that  with  our  spray  pumps  and  deadly 
sprays  many  crops  can  be  effectually  protected;  but  were  it  not 
for  those  other  insects  which  feed  upon  these  injurious  forms, 
what  an  enormous,  and,  in  some  instances,  futile  task  it  would  be ! 

Among  these  beneficial  insects  the  little  ladybird-beetles  of 
the  family  Coccinellidm  are  entitled  to  be  in  the  first  rank. 
Almost  all  these  beetles  and  larvae  feed  upon  plant-hce  and  scale 
insects.  Of  such  value  are  those  feeding  upon  scale  insects 
that  not  many  years  ago  several  Australian  species  were  imported 
into  Cahfornia  that  they  might  prey  upon  the  San  Jose  and  other 
scales.  One  of  these  was  eminently  successful  and  almost  com- 
pletely destroyed  the  cottony  cushion-scale. 

Of  those  feeding  upon  plant-lice,  one  of  the  most  common 
is  the  Nine-spotted  Ladybird  (Coccinellanovemnotata).  This 
beetle  is  about  one-fourth  of  an  inch  long,  with  black  head  and 
body.  The  wing-covers  are  orange-yellow  marked  with  nine 
black  spots  —  four  on  each  side  and  one  on  the  central  suture. 
The  larva  has  been  fancied  to  resemble  a  miniature  alligator; 
it  is  nearly  twice  as  long  as  wide,  almost  black,  marked  with 
bluish  and  orange  spots,  and  has  long  legs,  which  carry  it  around 
quite   rapidly.     The  beetles  hibernate  during  the  winter  and 

8 


BENEFICIAL  INSECTS,  PREDACEOUS  AND  PARASITIC         9 

come  forth  in  the  spring  and  lay  their  eggs  wherever  the  young 
will  be  able  to  find  food  when  they  hatch.  When  the  larva 
has  satisfied  its  ravenous  appetite  and  become  full  grown  it 
fastens  itself  to  a  leaf  or  twig,  —  seemingly  by  its  tail,  if  such. 


Fig.   1. — The  nine-spotted  ladybird  (Coccinella  iiovemnotata) ,  and  its  larva; 
enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

a  term  might  be  allowed,  —  transforms  to  the  pupa,  and  in  a  week 
or  ten  days  the  adult  beetle  emerges  from  the  pupal  skin.  This 
life-cycle  is  repeated  several  times  during  the  summer  season, 
before  the  fall  brood  enters  winter  quarters. 

Another  very  common  form  among  plant-lice  on  garden  truck 
is  the  little  Adalia  bipundata,  or  Two-spotted  Ladybird.      It  is 


Fig.  2. — ^The  two-spotted  ladybird  {Adalia  bipunctata):  a,  larva;  b,  mouth- 
parts  of  same;  c,  claw  of  same;  d,  pupa;  e,  adult;  /,  antenna  of  same; 
all  enlarged.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

slightly  smaller  than  the  preceding,  and  with  only  one  black  spot 
on  each  wing-cover  (Fig.  2). 


10         INSECT  PESTS  OF  FARM,  GABDEN  AND  ORCHARD 


Several  other  species,  in  the  genus  Hippodamia,  are  very- 
useful,  and  among  them  the  Convergent  Ladybird  {Hippo- 
damia convergens)  is  one  of  the  best  known.  Its  name  is  received 
from  two  white  dashes  on  the  black  thorax,  which  converge 
posteriorly.  The  thorax  has  also  a  white  margin,  and  there  are 
thirteen   black   dots   on   its   orange   wing-covers.     These   larvae 


Fig.  3. — The  convergent  ladybird  (Hippodamia  convergens) :  a,  adult;  b,  pupa; 
c,  larva;  enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

and  beetles  are  very  common  among  the  plant-hce  on  melon- 
vines,  and  are  an  important  factor  in  their  extermination.  They 
have  also  been  noted  for  eating  the  black  peach  aphis  and  many 
other  plant-lice. 

A  form  which  is  often  very  abundant  among  plant-hce  on  corn 
is  the  Spotted  Ladybird  (Megilla  maculata).     The  head,  thorax, 


Fig.  4. — The  spotted  ladybird  (Megilla  maculata):  a,  larva;  b,  pupa;  c,  adult; 
enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

and  wing-covers  are  a  dark  pink,  with  two  black  spots  on  the 
thorax  and   ten   on   the   wing-covers.     Such  numbers   of  these 


BENEFICIAL  INSECTS,  PREDACEOUS  AND  PARASITIC       11 


Fig.  5. — The  twice-stabbed  lady- 
bird (Chilocorus  bivulnerus). 
a,  adult;  b,  larva;  enlarged. 
(After  RUey.) 


little  fellows  have  frequently  been  found  huddled  together  under 
the  rubbish  at  the  base  of  some  tree  in  a  last  year's  cornfield 
that  they  might  be  taken  up  by  the  handful  without  difficulty. 
Many  other  species  feed  upon  plant-lice,  but  the  above  are  the 
most  common,  and  all  bear  a  resemblance  to  one  another,  being 
generally  orange  or  red  with  black  spots,  and  of  a  characteristic 

round  or  oval  form,  flattened  below, 
so  that  the  legs  may  be  drawn  in 
under  the  wing-covers. 

Those  ladybirds  which  feed  upon 
scales  are  much  smaller  and  are 
black,  though  sometimes  spotted 
with  red  or  orange. 

As  far  as  known,  there  is  no 
way  in  which  these  useful  allies 
may  be  encouraged  or  increased  in  numbers,  but  it  is  trusted 
that  the  above  may  give  such  a  brief  view  of  their  habits  that 
fewer  may  be  killed  through  ignorance  concerning  their  true 
worth. 

Syrphus-flies 

Besides  the  little  beetles  described  above  there  is  a  family 
of  flies,  the  Syrphida,  many  of  whose  larvae  feed  upon  plant- 
lice.  This  family  is  a  very  large  one,  and  thus  the  habits  of  its 
different  members  vary  considerably.  One  of  them,  the  drone- 
fly,  so  closely  resembles  a  honey- 
bee as  to  be  almost  indistin- 
guishable from  it.  The  larva  of 
this  fly  {Eristalis  tenax)  is  one 
of  the  common  rat-tailed  mag- 
gots which  are  found  in  putrid 
matter.  It  is  thought  that  the 
old  "  bugonia  "  superstition  of 
the  ancients  that  bees  came  from 

maggots  in  dead  animals,  etc.,  was  due  to  the  confusion  of  this 
fly  with  honey-bee. 

In  another  group  of  the  family,  the  adult  flies  of  which  also 
quite  closely  resembles  bees,  the  larvae  are  parasitic  in  the  nests 
of  honey-  and  bumble-bees,  feeding  upon  their  larvae. 


Fig 


Syrphus  ribesii;  enlarged. 


12  NSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

But  the  larvae  of  possibly  the  typical  portion  of  the  family, 
embracing  the  genus  Syrphus  and  its  near  allies,  are  entirely 
predaceous  upon  plant-Uce.  Rarely  can  a  colony  of  plant- 
lice  be  found  without  some  of  these  little  enemies  hard  after 
them. 

The  adult  syrphus-fly  is  a  very  striking  insect,  with  its  dark 
green  metallic  thorax,  and  abdomen  variously  banded  with 
yellow  and  black.  The  female  fly  lays  her  eggs  upon  some  plant 
bearing  plant-lice.  The  larvse  which  hatch  from  these  are  elongate, 
flattened  maggots,  about  one-half  an  inch  long,  with  hardly  a 
trace  of  a  head,  but  with  four  small  hooks,  which  serve  as  jaws, 
projecting  from  the  more  pointed  end  of  the  body.  These  mag- 
gots are  often  of  a  light-green  color,  and  so  like  the  color  of 
the  plants  as  to  render  them  most  difficult  to  recognize.  The 
young  larvse  at  once  commence  crawling  over  the  plant  in  search 
of  aphids,  and  as  soon  as  they  come  in  contact  with  one  it 
is  firmly  clasped  by  the  small  hooklets  until  the  juices  are  sucked 
from  its  body.  'In  this  manner  very  large  numbers  are  destroyed, 
a  single  maggot  of  the  American  Syrphus-fly  (Syrphus  americanus) 
having  been  observed  to  eat  twenty-five  apple  plant-lice  (Aphis 
pomi)  in  as  many  minutes.  When  the  larva  is  ready  to  pupate 
it  attaches  itself  to  a  leaf,  and  the  larval  skin  dries  up  and  forms 
a  case  or  puparium  inside  of  which  the  pupa  remains  until  it 
transforms  to  the  adult  fly. 

Though  most  of  these  larvse  feed  upon  plant-lice  upon  the 
leaves,  one  of  them,  the  Root-louse  Syrphus-fly  (Pipiza  radicans)^ 


Fig.  7. — ^The  root-louse  syrphus-fly  (Pipiza  radicans).  a. maggot;  6,  puparium; 
c,  fly.     (After  Riley.) 

lives  entirely  underground  during  that  stage,  and  feeds  upon 
the  root-lice  of  the  apple  and  the  grape.  None  of  this  family 
is  injurious,  and  as    a  large  portion  of  them  are  so  beneficial 


BENEFICIAL  INSECTS,  PREDACEOUS  AND  PARASITIC        13 

as  frequently  to  destroy  whole  broods  of  plant-lice,  they  should 
not  be  disturbed  in  their  good  work  if  possible  to  avoid  it. 


The  Ground-beetles 

If,  as  you  scrape  away  the  loose  chips  at  the  base  of  a  tree 
in  your  door-yard,  turn  over  an  old  log  in  the  woodland,  or  pick 
up  a  fallen  fence-rail,  you  will  scrutinize  the  inhal)itants  under 
these  shelters,  a  number  of  shining  black  beetles  varying  in  length 
from  one  fourth  to  ly^  inches  will  usually  be  noticed.  If  the  city 
reader  be  not  so  fortunate  as  to  be  familiar  with  or  have  access 
to  these  hiding-places,  he  may  find  large  numbers  of  the  beetles 


Fig.  8. — The  fiery  ground-beetle   (Calosoma  calidum).     a,  beetle;  h,  larva; 
c,  "  the  searcher  "  {Calosoma  scrutator).     (After  Riley.) 

under  any  electric  arc  light  during  the  warm  summer  evenings; 
for  there  they  are  having  a  sumptuous  banquet  upon  the  small 
flies  and  moths  attracted  by  the  glare.  They  are  rarely  seen 
at  large  during  the  day,  as  they  are  almost  exclusively  nocturnal 
insects,  and  from  their  habit  of  remaining  almost  entirely  in  or 
on  the  ground  they  are  usually  known  as  "  Ground -beetles."  As 
might  therefore  be  inferred,  they  are  exceedingly  valuable  to  the 
farmer  by  destroying  large  numbers  of  noxious  insects  which 
pass  a  part  or  all  of  their  existence  in  the  soil.  Besides  the 
glossy  black  forms  which  are  most  commonly  seen,  many  are 
brilhantly  marked  with  gold,  green,  purple,  and  iridescent  tints. 

The  Fiery  Ground-beetle  {Calosoma  calidum),   so   called  on 
account  of  the  wing-covers  being  dotted  with  bright  gold,  has 


14 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


many  times  been  of  great  assistance  in  helping  to  rid  a  corn-field 
of  cutworms.  The  larvae  of  this  insect  are  about  one  inch  in 
length,  of  a  dark  brown  color,  with  the  skin  of  a  hard,  horny 
texture  like  that  of  the  beetle.  They  have  strong,  prominent 
jaws,  and  at  the  posterior  end  of  the  body  is  a  forked  appendage 
looking  much  like  another  pair  of  jaws.  It  is  not  only  surpris- 
ing that  these  larvae  will  eat  so  large  a  number  of  cutworms 
as  they  have  frequently  been  known  to  do,  but  that  they  will 
dare  to  attack  such  a  formidable  creature  fully  three  or  four 
times  as  large  as  themselves,  but  their  assault  is  sharp  and 
vigorous,  and  a  single  larva  has  often  been  seen  to  kill  and  eat 
several  full-grown  cutworms  in  a  short  time.  Many  instances 
of  the  good  work  of  this  beetle  are  on  record,  among  which  one 
by  the  late  Professor  J.  A.  Lintner  may  be  cited,  where  he  found 
them  eating  large  numbers  of  the  corn- 
crambus — sometimes  locally  known  as  the  corn 
bud-worm.  Another  somewhat  larger  beetle, 
called  by  Professor  J.  H.  Comstock  "  the 
Searcher  "  (CaZosoma  scrutator)  y  and  in  fact 
one  of  the  largest  of  the  family,  is  a  brilliant 
metallic  green,  bordered  with  a  dark  purplish- 
blue,  and  has  the  good  quality  of  having  a 
very  particular  appetite,  causing  it  to  kill  large  numbers  of  cater- 
pillars, but  to  eat  only  part  of  each. 

While  in  the  earth  as  pupse   large   numbers  of   the    Colorado 
potato-beetles  are  destroyed   by   members  of   this  family,   and 


Fig.  9. — Lebia  gran 
dis.   (After  Riley.) 


Fig.   10. — The  murky  ground-beetle   (Harpalvs  caliginosus) :  adult  at  left; 
a,  larva;  b,  head  of  same;  c,  mandible.     (After  Riley.) 

one  species,  Lehia  grandis  which  is  peculiar   in   that  the  wing- 
oovers  are  somewhat  abbreviated,    thus  leaving  the  tip  of  the 


BENEFICIAL  INSECTS,  PREDACEOUS  AND  PARASITIC        15 


abdomen  exposed,  has  been  noticed  on    the    plants   eating    the 
eggs  and   young  larvae  of  this  old  potato  pest. 

Another  valuable  species  is  one  called  by  Dr.  Riley  the 
Murkej^  Ground-beetle  (Harpalus  caliginosus) .  Its  larva  is  of 
considerable  assistance  to  fruit-growers  by  eating  large  numbers 
of  curculio  larvae  which  it  secures  from  the  plums  after  they 
have  fallen  to  the  earth.  From  a  glance  at  its  formidable  jaws, 
Fig.  10  h — c,  it  is  easy  to  conjecture  the  fate  of  many  a  curculio  grub. 
Thus  here  again  are  found  some  "  bugs  "  that  are  friends  and 
not  foes,  worthy  of  all  the  protection  that  can  be  afforded  them, 
and  well  repaying  such  careful  observation  of  their  habits  as  may 
be  bestowed  upon  them. 

Insect  Parasites 

Though   large  numbers    of    injurious    insects    are    annually 
destroyed  by  those  which  are  purely  predaceous  upon  them,  many 
more  succumb  to  those  minute  forms  which  live  parasitically 
within   them.      A    few 
of    these  parasites    be- 
long to  the  order  Dip- 
tera,  or    true  flies,  but 
most  of  them  are  classed 
in  the  order    Hymeno- 
ptera,  in  which  order  are 
also  included  the   saw- 
flies,  ants,    wasps,  and 
bees. 

Of  the  half-dozen 
f  amihes  of  hymenopter- 
ous  parasites  one  of  the 
largest  and  most  bene- 
ficial is  that  of  the 
Ichneumon-flies.  The  illustrations  will  best  show  the  form  and 
structure  of  these  insects,  w^hich  the  casual  observer  will  hardly 
be  able  to  distinguish  from  other  families  of  the  group.  But 
it  will  be  noticed  that  the  fine  veins  of  the  wings  vary  considerably 
in  the  different  parasites  figured  and  it  is  by  these  that  the 
entomologist  is  enabled  to  separate  the  different  groups  and 
often  to  identify  the  species  at  a  glance.    Both  this  and  the  follow- 


FiG.  11. — Maggots  of  Pimpla  itiqiustlnr,  a 
parasitic  Ichneumon-fl}',  feeding  on  a  cater- 
pillar which  had  spun  its  cocoon  and  was 
ready  to  pupate. 


16 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


ing  family  are  peculiar  in  having  an  exceedingly  long  ovipositor 
or  egg-tube,  of  which  they  make  a  very  good  use.  It  is  with 
this  extensile  tube  that  the  female  deftly  punctures  the  skin 
of  some  unsuspecting  caterpillar,  and  under  it  inserts  her  eggs. 
In  a  few  days  there  hatch  from  these  a  host  of  young  maggots 
which  feed  upon  the  juices  and  tissues  of  the  caterpillar,  but  are 
seemingly  careful  to  avoid  injuring  any  of  its  vital  organs,  for  as 
soon  as  the  caterpillar  reaches  its  full  growth  it  changes  to  a 
pupa,  apparently  unaffected.  When  the  maggots  have  reached 
their  full  size  each  spins  up  a  small  silken  cocoon  inside  the  pupa, 
entirely  filling  up  its  now  dead  shell,  and  instead  of  a  beautiful 
moth  appearing  in  the  spring,  a  horde  of  small  flies  are  seen  to 
emerge  from  round  holes  in  the  side  of  the  pupa,  or  cocoon. 

Thus  laige  numbers  of  such  pests  as  the  apple-tree  tent-cater- 
pillar (Malacosoma  americana),  hagworms,  {Thyridopteryx 
ephemercef omits) )   caterpillars  of    the    swallow-tailed    butterflies 

which  feed  upon  parsley,  car- 
rots, etc.,  and  a  host  of  others, 
are  consumed  by  members  of 
this  family. 

Those  belonging  to  the 
genus  Ophion  are  partial  to 
the  large  American  silkworms 
which  produce  some  of  our 
largest  and  most  beautiful 
moths,  and  difficulty  is  fre- 
quently experienced  in  rear- 
ing a  desired  number  of  moths 
on  account  of  the  large  per- 
cent of  cocoons  parasitized. 
The  species  of  the  family 
Braconidm  are  very  similar  to 
those  of  the  preceding  one, 
and  contain  some  equally  ben- 
The  long-tailed  Ophion  {Ophion  eficial  insects,  feeding  as  they 
maggo  ,  ^^  upon  such  pests  as  the  cod- 
ling moth,  webworms,  plum- 
curculio  grubs,  plant-lice,  etc.  Some  of  the  more  common  forms 
of  this  family  belong  to  the  genus  Microgaster,  and  their  small 


Fig. 12 

macrurum).     a,     adult;     b, 
enlarged.     (After  Riley.) 


BENEFICIAL  INSECTS,  PREDACEOUS  AND  PARASITIC       17 

white  cocoons  may  frequently  be  seen  almost  covering  one  of  our 
large  tomato-  or  tobacco-worms  (see  page  220 ) ,  the  pupse  of  which 
are  often  known  as  "horn-blowers."  Many  mistake  these  cocoons 
for  the  eggs  of  the  worms,  and  therefore  destroy  some  of  their 
best  friends.  Though  some  thus  spin  their  cocoons  on  the  outside 
of  the  host,  others  remain  inside  of  the  parasitized  insect  until  the 
adult  fly  emerges.  Thus  dead  plant-lice  may  often  be  found  with 
a  large  round  hole  in  the  abdomen  —  the  only  evidence  of  where 
one  of  these  parasites  has  emerged.  The  Chalcis-flies,  Chalcididcv, 
which  comprise  another  closely  related  family,  are  often  exceed- 
ingly minute  insects,  sometimes  not  over  one  one-hundredth  of 
an  inch  long.  They  are  generally  of  a  metallic  black  color,  and 
the  usual  veins  of  the  wings  are  almost  entirely  absent.  Many 
of  these  flies  are  parasitic  upon  plant-lice,  while  a  large  number 
of  their  larvae  live  and  mature  in  the  eggs  of  other  insects. 

Very  similar  to  the  chalcis-flies  in  the  habits  of  infesting 
plant-lice  and  insect  eggs 
are  some  even  smaller 
insects — in  fact  the  small- 
est known,  the  largest  being 
rarely  over  one-twenty-fifth 
and  the  smallest  only  six-or- 
seven  one-thousandths  of  an 
inch  in  length — with  a  cor- 
respondingly tremendous 
and  unpronounceable  name, 
known  to  science  as  the  Pro- 
dotrypidoe.  During  the  last 
half  century  the  American 
farmer  has  been  compelled 
to  contend  with  an  increas- 
ing number  of  insect  pests.  Fig.  13. -A  plant-louse  parasite  (Aphidim 
°_  ^         '        avenapms) ,  snowing  above  the  parasitized 

which  now   and  then  have       louse  from  which  it  has  issued.     (Copied 
become  veritable  scourges.       from  J.  B.  Smith.) 
Every  now  and  then  we  hear  of  communities  assembling  for  prayer 
and  fasting  to  appease  the  Almighty,  whose  wrath  has  hurled  a  new 
insect  plague  against  them,  but  such  a  procedure  is  by  no  means  as 


18         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

common  as  formerly,  and  little  reflection  will  show  that  these 
scourges  are  entirely  due  to  natural  causes.  In  fact  they  are  very 
largely  brought  about  by  man  himself.  Some  of  these  pests  are  due 
to  the  fact  that  in  trying  to  subdue  nature  by  clearing  and  cultivat- 
ing the  land,  man  has  deprived  the  insects  of  their  natural  food 
plants.  They  must,  therefore,  needs  feed  upon  that  which  is  sub- 
stituted by  him,  and  as  it  is  less  abundant  than  the  former  wild 
vegetation,  the  number  of  insects  and  the  injury  they  inflict  are 
more  apparent. 

By  far  the  larger  number  of  our  worst  pests,  however,  are  those 
which  come  to  us  from  foreign  shores.  Foreign  insects  are  con- 
stantly being  imported  in  one  way  or  another,  sometimes  being 
already  established  pests  in  other  lands  and  sometimes  only  be- 
coming so  under  their  new  surroundings.  These  are  even  more 
injurious  than  those  native,  for  whereas  many  of  our  native  birds, 
insects,  and  diseases  constantly  prey  upon  native  insects  and  thus 
keep  their  numbers  in  check,  the  enemies  of  imported  pests  rarely 
accompany  them,  and  they  thus  increase  at  an  alarming  rate  and 
do  enormous  damage  before  they  are  attacked  by  the  natural 
enemies  of  similar  native  pests.  It  is  in  the  case  of  these  imported 
pests  that  the  value  of  parasitic  and  predaceous  insects  is  most 
apparent.  In  an  effort  to  make  use  of  them  to  fight  the  gypsy 
and  brown-tail  moths  in  New  England,  the  U.  S.  Bureau  of  Ento- 
mology has  for  several  years  been  importing  large  numbers  of  the 
parasites  and  predaceous  enemies  of  these  pests  and  liberating 
them  in  affected  regions,  thus  carrying  on  a  practical  experiment 
on  a  large  scale  which  may  show  the  importance  of  these  parasites 
in  combating  imported  pests. 

Even  with  our  native  pests,  however,  we  have  frequent  exam- 
ples of  the  value  of  parasitic  and  predaceous  enemies.  Thus  the 
southern  grain  louse,  or  ''green  bug,"  was  soon  brought  under 
control  by  the  myriads  of  little  parasites  which  preyed  upon  it 
(see  page  140),  and  these  were  artificially  transported  for  some 
distance  and  liberated  in  large  numbers.  Though  these  efforts  at 
the  distribution  of  this  parasite  may  be  open  to  some  question 
as  to  their  'effectiveness,  other  parasites  have  been  successfully 


BENEFICIAL  INSECTS,  PREDACEOUS  AND  PARASITIC       19 

distributed,  and  there  can  be  no  question  that  before  long  we 
shall  come  better  to  understand  how  we  may  make  use  of  these 
valuable  alhes,  and  some  day  we  may  be  able  to  duphcate  the 
apparent  miracle  by  which  Dame  Nature  sweeps  away  an  insect 
plague  in  a  few  days  with  the  aid  of  these  apparently  insignificant 
parasites. 


CHAPTER  III 

STRUCTURE  AND  DEVELOPMENT  OF  INSECTS 

The  more  experience  the  farmer  has  with  insect  pests,  the 
more  he  comes  to  reahze  that  if  he  would  successfully  combat 
them  he  must  have  a  certain  amount  of  knowledge  concerning 
their  structure  and  growth. 

In  general,  the  artificial  means  which  may  be  effectually 
used  to  combat  an  insect  pest  will  depend  more  or  less  upon 
the  anatomical  structure  of  the  insect,  while  control  by  general 
methods  of  culture  will  depend  upon  a  knowledge  of  the  peculiari- 
ties of  its  life-history.  The  value  of  a  proper  understanding  of 
these  important  factors  in  insect  control  is  therefore  apparent. 

General  Structure  of  an  Insect 

The  body  of  an  insect  is  composed  of  three  separate  parts 
the  head,  thorax,  and  abdomen  (Fig.  14),  each  of  which  is  com- 
posed of  several  rings  or  segments. 
To  the  head  are  attached  the 
jointed  antennae,  or  feelers,  the 
compound  eyes,  and  the  mouth- 
parts,  which  are  described  below. 
Each  of  the  three  segments  of 
the  thorax  bears  a  pair  of  legs, 
and  adult  insects  usually  possess 
one  or  two  pairs  of  wings  upon 
the  last  two  segments  of  the 
thorax.  The  abdomen  is  com- 
posed of  nine  or  ten  segments, 
Fig.   14. — Honey-bee,  showing  the    ,     ,     i  , 

three  principal  regions  of  the  body   but   bears   no   appendages   save 

of  an  insect:— /i,  head;  </(,  thorax;    the  ovipositor  of  the  females  of 

abd,  abdomen.  ,    •  , 

certam  orders. 

Harvest-mites,  or  "  daddy-long-legs,"  sow-bugs,  thousand- 
legged    worms,    and    related   forms    are   often    popularly    called 

20 


STRUCTURE  AND  DEVELOPMENT  OF  INSECTS 


21 


insects,  but  all  of  them  can  readily  be  distinguished  from  true 
insects  by  their  possessing  more  than  six  legs,  the  harvest-mites 
and  spiders  having  eight  and  the  otlicrs  ten  or  more. 


How  Insects  Grow 

With  rare  exceptions  insects  hatch  from  eggs  laid  by  the 
adult  females.  Upon  hatching  they  are  but  little  larger  than 
the  eggs,  and  often  bear  but  little  resemblance  to  their  parents. 
Thus  the  young  caterpillar  woukl  never  be  recognized  as  the 
immature  stage  of  the  butterfly  by  one  unfamiliar  with  its  trans- 


FiG.  15. — Complete  metamorphosis.  The  different  stages  of  the  corn  ear- 
worm  {Chloridea  obsoleta  Fab.):  a,  eggs  on  corn-silk;  h,  the  first  three 
larval  stages;  c,  pupa  from  below;  d,  same  from  above;  e,  adult  moth — 
all  enlarged;  h,  about  twice  natural  size. 

formations.  Grasshoppers  and  some  other  insects,  however,  upon 
hatching  from  the  egg  bear  a  marked  resemblance  to  the  adult 
form,  except  that  they  lack  wings. 


22  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHAR 

Complete  Metamorphosis.  —  When  the  caterpillar  hatches 
from  the  egg  it  at  once  commences  to  feed  and  grows  very 
rapidly,  but  before  long  an  obstacle  to  further  growth  arises. 
Unlike  higher  animals,  insects  possess  no  internal  skeleton  or 
framework  for  the  organs  of  the  body,  but  the  outer  skin  becomes 
hardened  and  to  it  the  muscles  and  ligaments  are  attached.  This 
hardening  of  the  skin  is  best  seen  in  the  horny  wing-covers  of  the 
beetles,  and  is  due  to  the  secretion  of  a  hard  substance  called 
chitin!  This  chitin  is  secreted  by  all  parts  of  the  skin  in  greater 
or  less  degree,  and  thus  forms  a  sort  of  shell  for  the  whole  body. 
Though  this  hardening  is  not  so  apparent  in  larvae  as  in  adult 
insects,  it  always  occurs  and  it  is  for  this  reason  that  when  the 
young  caterpillar  has  made  a  certain  growth  it  is  forced  to  shed  its 
skin,  which  refuses  to  expand  further,  in  order  to  develop  more 
fully.  Thus  the  skins  of  insects  are  shed  several  times  (see  Fig. 
15,  b), — usually  five  or  six,  but  sometimes  as  many  as  twenty,  this 
process  being  known  as  molting.  During  its  life  as  a  caterpillar, 
which  is  called  the  larval  stage,  and  during  which  it  is  called  a 
larva,  it  is  an  elongate,  worm-like  creature,  with  six  short, 
jointed  legs  on  the  three  thoracic  segments,  a  pair  of  fleshy  false 
legs  or  pro-legs  on  the  last  abdominal  segment,  and  probably 
several  pairs  of  pro-legs  between  these  and  the  true  legs.  No 
traces  of  wings  can  be  seen,  but  the  body  is  often  covered  with 
hairs,  spines,  or  warty  tubercles. 

With  the  next  molt  the  insect  changes  in  appearance  most 
radically,  becoming  a  pupa,  or  chrysalis,  as  this  stage  is  termed 
for  butterflies.  During  the  pupal  stage  the  insect  remains 
dormant  either  in  a  small  ceil  slightly  under  the  surface  of  the 
earth,  or  in  a  silken  cocoon  spun  by  the  caterpillar,  or  merely 
attached  to  the  food-plant  by  a  strand  of  silk  or  the  cast  larval 
skin.  In  many  of  the  Diptera, — the  order  including  flies,  mos- 
quitoes, gnats,  etc., — however,  the  last  larval  skin  is  not  shed, 
but  hardens  and  forms  a  case — called  a  puparium — within  which 
the  pupal  stage  is  passed. 

The  typical  pupa  (Fig.  15,  c,  d)  of  a  butterfly  or  moth  re- 
sembles neither  the  adult  insect  nor  the  larva,  is  of  a  more  or 
less  oval  shape,  with  the  wings  and  antennae  tightly  folded  at 
the  sides,  the  legs  drawn  up  snugly  together  under  them,  and  the 
head  and  mouth-parts  bent  upon  the  breast,  or  sternum,  though 


STRUCTURE  AND  DEVELOPMENT  OF  INSECTS 


23 


not  all  of  these  parts  are  always  recognizable,  the  legs  and  mouth- 
parts  being  sometimes  lacking.  Gradually  the  adult  insect 
develops,  and  at  last  the  pupal  skin  is  broken  open  and  the  airy 


■  r 


^.       ^ 


Fig.    16. — Incomplete  metamorphosis  of  a  bug    (Brachymena  4-pustiilata) : 
a,  eggs;  b,  adult  bug;  c,  ditlerent  stages  of  j'oung  bugs  or  nymphs. 

butterfly  emerges  to  enjoy  a  short  life  and  perpetuate  the  species. 
Such  a  series  of  transformations  is  that  commonly  found  among 
butterflies  and  moths  (Lepidopterd) ,  beetles  (Coleoptera),  flies 
(Diptera),  and  bees  {Hymenoptera),  and  is  known  as  a  complete 
metamorphosis.  All  of  these  insects  normally  pass  through 
four  stages,  egg,  larva,  pupa,  and  adult. 

Incomplete  Metamorphosis. — In  contrast  to  this  mode  of 
development  is  that  of  the  grasshoppers  (Orthoptera) ,  bugs 
(Hemiptera),  and  some  other  insects.  As  already  stated,  these 
are  much  like  the  adult  upon  emerging  from  the  egg.     With 


24  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

each  molt  they  become  larger  and  small  wing-like  pads  gradually 
appear  on  the  sides  of  the  thorax.     There  is  no  dormant  or  pupal 
stage,  the  adult  insect  differing  from  the  previous  stages  in  hav- 
ing fully  developed  wings,  being  larger,  and  often  by  an  accompany- 
mg  change  of  markings.     The  immature  stages  of  such  insects 
are  called  nymphs,   and  this  development  an  incomplete  meta- 
morphosis, having  but  three  stages,  egg,  nymph,  and  adult  (Fig.  16). 
The  time  occupied  by  the  complete  hfe-cycle  of  an  insect 
varies  from  a  week  or  ten  days  for  the  plant-hce  to  thirteen  or 
seventeen   years   for   some   cicadas,    and   is   entirely   dependent 
upon  the  habit  of  the  species  and  the  climate.     A  correct  knowl- 
edge of  the  exact  time  and  conditions  under  which  the  trans- 
formations occur  for  each  individual  insect  pest  is  therefore  often 
most  essential  when  seeking  means  for  its  control. 

How  Insects  Feed 
The  material  to  be  used  in  combating  a  given  insect  is  largely 

dependent  upon  the 
structure  of  its  mouth- 
parts.  Much  Paris 
green  is  wasted  upon 
insects  unable  to  eat  it 
and  which  it  will,  there- 
fore, never  kill. 

Insects  may  be 
roughly  di\aded  into 
two  classes,  those  which 
bite  and  those  which 
suck  their  food.  Among 
the  former  are  the 
beetles,  grasshoppers, 
the  larvae  of  butterflies 

-Front-view face  of  grasshopper  (5cHzto- and    moths      and       thp 
cerca  americana):  ant.,  antenna;  oc,  ocellus:  ,  "^""^'     ^°^       ^^^ 

ey.,  eye;  cl.,  clypeus;  Ibr.,  labrum,  or  upper  larvae  of  saw-flies;  and 
hp;  mxp.,  maxillary  palpus;  lab.j).,  labial  pal-  amouff  the  latter  arp 
pus;  ffaZ.,  galea,  lobe  of  maxilla;  fol  labium,  or,      "     «•  ^  ,      ^ 

under  hp.  buttertiies,    flies,    bees, 

and  bugs,  while  the 
larva  of  most  flies  and  bees  do  not  possess  mouth-parts  homo- 
logous with  those  of  the  above. 


Fig.  17. 


STRUCTURE  AND  DEVELOPMENT  OF  INSECTS 


25 


Biting  Mouth-parts. — •Mouth-parts  typical  of  those  of  biting 
insects  are  easily  seen  in  the  grasshopper  (Figs.  17  and  18).  In 
brief,  they  consist  of  an  upper  and  a  lower  lip,  between  which 
are  two  pairs  of  jaws  which  work  transversely.  The  upper  pair 
of  jaws,  or  mandibles,  are  stout,  short,  and  horny,  usually  sharp- 
ened at  the  tip,  slightly  serrated  at  the  margins,  and  flattened  at 
the  base.  The  lower  pair  of  jaws,  or  maxillce  are  longer,  not  so 
strong,  and  to  each  of  them  is  attached  an  accessory  lobe,  and  a 
jointed  style  called  a  palpus  or  feeler.  At  each  side  of  the  lower 
lip  is  another  palpus,  these  palpi  bearing  sensory  organs. 

Sucking  Mouth-parts. — In  the  sucking  insects  these  mouth- 
parts  are  prolonged  into  a  tube  through  which  the  juices  of  the 
food  plant — or  animal — are  sucked.     In  the  plant-lice  and  other 


Fig.  18. — A,  mouth-parts 
of  grasshopper  sep- 
arated to  show  posi- 
tion and  relation;  B, 
mouth-parts  dissected; 
Ibr.,  labrum;  md.,  man- 
dible; hyp.,  hypopha- 
rynx  or  tongue;  mx.p., 
maxillary  palpus;  lb  p  , 
labial  palpus;  lab.,  lab- 
ium; max.,  maxillae. 

bugs  the  lower  lip  is  elongated  so  that  it  forms  a  tube,  and  the 
maxillae  and  mandibles  consist  ot  long  hair-like  bristles,  or  seta?, 
enclosed  within  this  tube  (Fig.  20).  The  tip  of  this  beak  is  rested 
upon  the  surface  of  a  leaf  into  which  the  setae  are  thrust,  lacerat- 
ing the  tissue,  and  by  a  pumping  process  of  the  mouth  the 
juices  are  sucked  up  through  the  beak.  The  structure  of  the 
mouth-parts  of  the  various  orders  of  sucking  insects  varies  con- 
siderably, but  all  agree  in  that  they  suck  up  the  food  in  a  liquid 
state.  Any  application  ot  a  poisonous  spray  to  the  surface  of 
toliage  will  be  of  no  avail  against  them,*  though  sure  death    to 

-  Liquid  poisoned  baits,  used  for  house-flies,  adults  of  onion-maggots,  etc., 
form  an  exception  to  this  rule. 


26 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


most  biting  insects  which  chew  the  leaves.     Sucking  insects  must 
therefore  be  killed  by  other  means. 

How  Insects  Breathe 

Along  the  side  of  a  caterpillar  or  larva,  on  one  thoracic  seg- 
ment and  on  each  abdominal  seg- 
ment except  the  last,  is  a  small  oval 
spot,  in  the  centre  of  which  is  a  slit 
closed  by  two  membranous  lips. 
These  apertures  are  called  spiracles 
or  stigmata  (Fig.  21  sp.),  and  are 
the  openings  of  the  respiratory  sys- 
tem. Similar  openings  are  to  be 
found  in  all  insects,  though  not  so 
easily  seen  in  the  adults.  Connect- 
ing these  spiracles  is  a  pair  of  tubes 
on  each  side  of  the  body,  through- 
out its  length,  from  which  branch  off 
smaller  tubes  to  all  of  its  organs 
and  tissues.  Fresh  air  is  inhaled 
to  all  parts  of  the  body  through 
these  tubes  (Fig.  21,  tr). 

The  blood  of  insects  does  not 
circulate  through  any  system  of  tubes 
as  it  does  in  the  higher  animals. 
Along  the  middle  of  the  back, 
above  the  alimentary  canal,  is  a 
long  tube  popularly  called  the  heart 
(Fig.  23,  d.  v.).  This  heart  is  com- 
posed of  a  number  of  chambers, 
each    of    which    is    furnished   with 

Fig.  19.-Cicada,  showing  mouth-  ^ide  valves  for  admitting  blood  from 
parts  of  a  bug,  a  sucking  insect;  the  bodv-cavity,  Theblood  coming 
^isS  'r  ftfTpo'S"  be-  i"to  the  heart  from  the  body-cavity 

tween  forelegs;  b,  head  removed:  is     propelled     forward    toward     the 

^■iblSlti-'-tm'iilty  S;  head,  where  it  again  flows  into  the 

lab.,  labium.  body-cavity.     Thus  various  currents 

of  blood  are  maintained  throughout  the    body,    but  other  than 

the  heart  there  is  no  system  of  blood-vessels,  the   blood    merely 

fillmg  the  body-cavity  arovmd  and  through  the  various  organs  and 


STRUCTURE  AND  DEVELOPMENT  OF  INSECTS 


27 


tissues.     Constantly    flowing    around    tne    respiratory    tubes    or 
tracheae,  the  blood  is  quickly  and  thoroughly  purified,  though  the 


-y^P 


Fig.  20. — Mouth-parts  of  a  plant- 
louse:  a,  the  jointed  beak;  b,  the 
lancets,  much  enlarged;  c,  antenna; 
d,  foot.     (After  J.  B.  Smith.) 


Fig.  21. — Diagram  of  tracheal 
or  breathing  system  of  an 
insect:  sp.,  spiracles;  tr., 
trachea.     (After  Kolbe.) 


exact  manner  in  which  this  is  done  is  not  definitely  known.  The 
respiratory  system  has  absolutely  no  connection  with  the  mouth 
or  pharynx  (Fig.  23,  ph),  as  have  the  lungs  of  the  higher  animals, 


Fig.  22. — Ideal  section  through  an  insect:  a,  aHmentary  canal;  h,  heart; 
n,  nerve  cord;  s,  spiracle;  t,  tracheal  tubes;  I,  legs;  w,  wings.  (From 
Riverside  Natural  History.) 


28 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


and  if  an  insect  is  to  be  suffocated,  it  must  be  done  by  closing  the 
spiracles.  It  is  in  this  way  that  tobacco-dust,  lime,  pyrethrum, 
and  similar  insecticides  kill  sucking  insects,  by  penetrating  the 
spiracles  and  choking  the  tracheal  system.  Whale-oil  soap, 
^"7  1^ 


;CL.V 


T^fT 


Fig.  23. — Internal  anatomy  of  silk-worm,  from  photo  of  Azoux  Model: 
A,  upper  or  dorsal  bodywall  seen  from  within;  B,  the  back  of  the  silk- 
worm removed,  showing  alimentary  canal;  C,  alimentary  canal  removed, 
showing  nervous  system  and  tracheal  trunks;  tr.,  trachea;  d.v.,  dorsal 
vessel  or  heart;  'ph.,  pharynx  or  mouth;  su.,  supra-oesophageal  ganglion; 
sp.sp.,  spiracles  or  breathing  pores;  n.,  nerve  cord;  tr.t.,  tracheal  trunk; 
oes.,  oesophagus  or  throat;  cr.,  crop;  s.g.,  silk  gland;  pro.,  proventriculus; 
St.,  stomach;  h.i.,  hind  intestine. 

kerosene  emulsion,  and  the  other  "contact"  insecticides,  or  "irri- 
tants," also  stop  up  the  spiracles  and  thus  cause  death,  but  they 
may  act  as  "irritants,"  penetrating  the  skin  and  thus  killing  the 
insect.  When  insects  are  killed  by  means  of  a  gas  such  as  carbon 
bisulfide  or  hydrocyanic  acid  gas,  they  are  asphyxiated  by  a  substi- 
tution of  these  gases  for  air,  the  same  as  are  the  higher  animals. 

Though  arsenical  poisons  are  generally  used  as  sprays  for  biting 
insects,  soft-bodied  caterpillars  and  similar  larvae  are  often  killed 
by  the  use  of  contact  insecticides,  which  affect  them  the  same  as 
sucking  insects. 

The  reader  will  observe  that,  almost  without  exception,  the 
remedies  advised  for  different  insect  pests  in  the  following  pages 
are  determined  by  some  peculiarity,  either  of  structure  or  develop- 
ment, of  the  insect  to  be  combated. 


CHAPTER  IV 
FARM  METHODS  FOR  THE  CONTROL  OF  INSECTS 

The  old  adage  "an  ounce  of  prevention  is  worth  a  pound  of 
cure,"  is  never  more  true  than  in  the  control  of  insect  pests,  for  in 
almost  all  cases  their  successful  control  is  by  prevention  before  the 
injury  has  become  acute,  rather  than  by  destruction  after  the 
injury  is  noticeable.  Even  insecticides  must  be  applied  so  that 
they  will  kill  the  insect  before  it  has  done  serious  damage,  for  after 
damage  is  apparent  it  is  too  late  to  prevent  the  injury,  so  that 
the  use  of  insecticides  for  the  protection  of  crops  must  be  of  a  pre- 
ventive nature.  In  the  control  of  insects  affecting  the  staple 
crops  which  are  grown  over  immense  areas  with  a  small  profit  per 
acre,  it  is  evidently  unpracticable  to  use  insecticides  and  mechani- 
cal methods  which  are  used  in  the  orchard  and  garden.  For  the 
control  of  staple  crop  insects  we  are  compelled  to  rely  largely  on 
general  methods  of  farm  management,  which  may  be  carried  out 
in  connection  with  the  farm  operations  at  small  cost,  and  which 
will  fatally  interfere  with  the  development  of  the  insect  to  be  con- 
trolled. To  do  this  intelligently  involves  an  understanding  of 
the  life-history  of  the  insect,  revealing  the  time  at  which  it  is  most 
vulnerable  and  the  reason  for  the  method  of  control  advised.  The 
importance  of  such  a  knowledge  of  the  life-histories  and  habits  of 
insects  to  be  controlled  by  farm  methods  will  become  apparent 
in  the  following  chapters. 

Though  the  insects  affecting  staple  crops  are  more  largely  con- 
trolled by  farm  methods,  those  of  the  garden  and  orchard  may  be 
much  reduced  by  the  intelligent  application  of  the  same  princi- 
ples, and  he  who  adapts  his  methods  so  as  to  prevent  insect  attack 
wiU  be  much  more  successful  than  one  who  depends  upon  artificial 
means  for  their  destruction. 

Looking  Ahead. — In  planning  the  management,  of  their  land 
and  crops  for  the  coming  season,  few  farmers  consider  the  effect 

29 


30  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

which  any  given  procedure  will  have  upon  the  injurious  insects  with 
which  they  may  have  to  contend.  A  field  which  has  for  several 
years  been  in  wheat,  corn,  or  tobacco,  may  be  sown  with  some 
other  crop  for  the  sake  of  soil  improvement,  but  how  often  is  it 
considered  necessary  to  rotate  crops  to  avoid  insect  pests?  In 
most  cases  they  are  left  out  of  consideration  until  a  crop  has  been 
seriously  injured  and  the  necessity  for  a  change  of  methods  thus 
impressed  on  the  owner. 

Particularly  while  crops  are  j'^oung  they  should  be  frequently 
inspected  and  examined  for  any  evidence  of  the  pests  which  com- 
monly affect  them.  Be  prepared  to  attack  any  pests  which 
may  be  found  upon  their  first  appearance,  for  many  of  the 
most  destructive  insects  increase  with  amazing  rapidity,  and 
when  they  have  become  abundant  it  is  too  late  to  prevent  the 
damage. 

Cwp  Rotation. — One  of  the  most  important  factors  in  insect 
control  is  the  rotation  of  crops  in  such  a  manner  that  the  same 
crop  shall  not  be  grown  continuously  on  the  land.  In  many 
cases  a  yearly  rotation  will  be  advantageous,  while  a  frequent 
rotation  will  always  be  found  beneficial.  Many  insects  feed  on 
one  crop  only.  It  is  evident,  therefore,  that  if  they  hibernate  in 
or  near  the  field  which  it  occupied  and  it  is  then  planted  to  the 
same  crop  the  next  year,  they  will  be  furnished  food  for  their 
increase,  while  if  the  field  be  planted  in  a  crop  not  attacked  by 
the  insects  peculiar  to  the  previous  crop  they  will  have  to  migrate 
from  it,  with  probably  a  very  considerable  mortality  as  a  conse- 
quence, for  they  will  radiate  in  all  directions  and  many  will  die 
before  finding  food,  while  many  more  will  have  been  destroyed 
in  the  preparation  of  the  old  field  for  the  new  crop. 

The  western  corn  root-worm  may  be  entirely  controlled  by  a 
rotation  so  that  corn  is  never  grown  two  successive  years  on  the 
same  land,  for  the  larvse  feed  only  on  the  roots  of  corn,  and  when 
it  is  followed  by  a  small  grain,  grass,  or  clover,  they  are  starved 
out.  Injury  by  the  Hessian  fly  to  wheat  is  also  very  materially 
reduced  where  a  frequent  rotation  is  practised,  as  is  that  of  the 
chinch-bug  on  corn. 

Care  should  be  exercised  to  arrange  a  rotation  in  which  crops 
nearly  related  botanically  do  not  follow  each  other,  for  usually 
the  same   insects  attack  them.     Thus  white  grubs,   cutworms, 


FARM  METHODS  FOR  THE  CONTROL  OF  INSECTS  31 

and  wireworms  live  normally  in  grass  land,  and  where  it  has  not 
been  plowed  for  several  years  the}'  often  become  exceedingly 
abundant.  If  the  sod  be  then  turned  under  and  the  land  planted 
to  corn  these  insects  will  attack  the  corn,  and  as  there  are  rela- 
tively few  plants  to  the  number  of  insects  which  were  feeding 
upon  the  grass,  the  injury  will  usually  be  serious.  To  avoid 
this,  sod  land  should  be  planted  in  a  small  grain,  buckwheat, 
potatoes,  or  some  crop  not  affected  by  these  pests.  Similarly, 
the  insects  which  affect  cabbage  usually  feed  on  all  the  cole  crops, 
and  turnips,  radishes,  etc.,  following  cabbage  will  be  liable  to 
injury  b}^  the  same  pests.  Clovers,  cowpeas,  and  other  leguminous 
crops  become  of  importance  in  rotation  in  this  connection,  as 
the3^  are  not  usually'  attacked  by  the  insects  affecting  other  crops, 
and  of  course  are  widely  used  in  every  good  rotation  for  the  pur- 
pose of  storing  nitrogen  in  the  soil  through  their  root  tubercles. 

Time  of  Planting. — Planting  crops  so  that  they  may  avoid 
the  greatest  abundance  of  their  worst  insect  enemies  is  often  the 
best  method  for  their  protection.  Late-sown  wheat  is  usually 
exempt  from  the  attack  of  the  Hessian-fly  (see  page  119) 
and  late-planted  corn  is  much  less  affected  by  the  stalk-borer 
(see  page  82)  than  that  planted  earlier.  On  the  other  hand 
early  planting  of  early-maturing  varieties  often  enables  the  crop 
to  mature  before  its  pests  become  most  abundant.  Thus  early 
planting  and  earl}^  varieties  are  of  the  greatest  importance  in 
preventing  injury  by  the  cotton  boll  weevil,  the  cotton  boll- 
worm  and  corn  ear-worm,  and  early  varieties  of  peas  escape  the 
injury  of  the  pea  aphis. 

Weeds. — Many  insects  feed  upon  some  common  weed  in  one 
stage  while  in  another  stage  they  are  injurious  to  a  cultivated 
crop.  Thus  the  flea-beetles  feed  upon  the  roots  of  solanaceous 
weeds  during  the  larval  stage,  while  the  adults  attack  all  sorts  of 
garden  crops.  In  many  cases  caterpillars,  such  as  the  salt  marsh 
caterpillar,  army  worms,  the  white-lined  sphinx  moth,  and 
grasshoppers  multiply  upon  weeds  growing  in  neglected  fields 
until  they  overflow  and  destroy  crops.  Many  insects  feed  on 
weeds  during  the  early  part  of  the  season  or  after  the  crop  which 
they  injure  is  harvested,  so  that  the  destruction  of  these  weeds 
may  often  considerabl}^  shorten  their  breeding  season  or  increase 
their  mortality.     Thus  the   corn  root-aphis  lives  on   the  roots 


Fig.  24. — Above,  a  pooih  koj)t  roadside  with  rail  fence  overgrown  with  brambles, 
thus  affording  protection  for  kirge  numbers  of  destructive  insects  during 
winter.  Below,  a  well  kept  roadside,  offering  the  least  protection  possible  for 
destructive  insects.     (After  Webster,  U.  S.  Dept.  Agr.). 

32 


FARM  METHODS  FOR  THE  CONTROL  OF  INSECTS        33 

of  smartweed  and  other  weeds  and  grasses  until  corn  is  available, 
and  cutworms  feed  on  whatever  vegetation  is  found  before  a 
crop  is  planted.  In  this  connection  "volunteer"  plants  should 
be  classed  as  weeds,  as  they  frequently  furnish  food  for  insects 
in  the  same  way.  Thus  the  cotton  boll  weevil  feeds  on  volunteer 
cotton  in  early  spring  and  the  Hessian-fly  on  vohmteer  wheat 
in  late  summer  and  early  fall.  Such  useless  trees  as  wild  cherry 
and  seedling  apple  trees  might  also  be  considered  as  weeds,  as  they 
harbor  many  of  the  insect  pests  of  our  orchards  and  should  be 
destroyed  as  far  as  possible. 

Fertilization  and  Culture. — Although  there  is  evidence  that 
under  some  conditions,  kainit,  lime  and  nitrate  of  soda  may 
have  some  direct  effect  on  insects,  it  is  probable  that  their  chief 
importance  is  so  to  stimulate  the  plant  that  it  will  not  be  subject 
to  insect  attack  or  will  grow  in  spite  of  some  injury.  It  is  well 
known  that  plants  which  have  been  weakened  from  any  cause 
whatsoever  are  much  more  subject  to  the  attacks  of  insects  and 
diseases,  and  it  is  therefore  obvious  that  plants  which  have  had  a 
vigorous  growth  and  which  will  mature  rapidly  will  much  better 
withstand  insect  attack.  Thorough  preparation  of  the  soil 
before  planting,  liberal  fertilization,  and  thorough  culture  are 
most  important  in  growing  a  crop  in  spite  of  its  insect  enemies. 
In  many  cases  liberal  fertilization  and  culture  will  mature  a  good 
crop  where  under  poorer  care  it  would  have  succumbed  to  insect 
injury.  In  general,  land  covered  with  barnyard  manure  presents 
more  favorable  conditions  for  the  hibernation  of  insects  than  that 
fertilized  with  mineral  fertilizers,  but  unless  this  is  very  appreciably 
the  case,  the  manure  will  usually  be  preferred  when  it  is  available. 

Clean  Farming. — After  a  crop  has  been  harvested  there  is 
usually  some  portion  of  the  plant  which  is  allowed  to  remain 
on  the  land.  In  this  refuse  the  insects  peculiar  to  the  crop  often 
feed  and  multiply  until  killing  frost  and  then  hibernate  over 
winter,  ensuring  injury  to  similar  crops  on  the  same  land  the 
next  year.  The  wheat  joint  worm  and  the  corn  stalk-borer 
both  winter  in  the  stubble  of  those  crops,  and  the  chinch-bug 
commonly  hibernates  in  the  butts  of  corn  stalks.  All  of  these 
may  be  largely  controlled  by  burning  the  stubble.  Possibly 
the  most  important  means  of  control  of  the  cotton  boll  weevil 
is  the  destruction  of  the  stalks  in  the  fall  as  soon  as  the  cotton 


34 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


can  be  picked,  thus  preventing  the  weevils  feeding  and  starving 
them  out  before  they  are  ready  to  hibernate,  and  removing  the 
shelter  for  hibernation.  For  this  reason  all  the  remnants  of  a  crop 
such  as  stubble,  vines,  leaves,  or  stumps,  as  may  be,  should  be 
removed  from  the  field  as  soon  after  it  is  harvested  as  possible. 
Many  insects  hibernate  in  such  rubbish  and  this  fact  may  some- 
times be  utilized  by  thoroughly  cleaning  a  field  and  leaving  one  or 
two  piles  of  rubbish  in  which  many  of  the  insects  will  assemble 


Fig.  25. — A  field  of  cabbage  stumps  in  midwinter,  affording  ideal  condi- 
tions for  the  hibernation  of  cabbage  pests. 

for  hibernation,  and  which  may  then  be  burned  or  otherwise 
destroyed.  Many  cabbage  insects  hibernate  under  the  old  stumps 
and  leaves  and  will  congregate  in  piles  of  them.  Premises  upon 
which  the  fence  rows  are  kept  free  from  weeds  and  grass  and  the 
fields  are  cleaned  up  and  plowed  as  soon  as  possible  after  a  crop  is 
removed,  usually  suffer  much  less  from  insect  pests  than  those  of 
more  easy-going  neighbors. 

Burning. — Cleaning  up   of  stubble    and   of  wild    vegetation 
which  furnishes  food  and  shelter  for  insects  may  often  be  accom- 


FARM  METHODS  FOR  THE  CONTROL  OF  INSECTS         35 

plished  by  burning.  The  burning  over  of  grass  land  aids  greatly 
in  the  control  of  army  worms,  chinch-bugs,  grasshoppers  and 
plant-lice,  while  the  burning  of  the  stubble  will  largely  control 
the  wheat  jointworm.  Strawberry  beds  are  sometimes  burned 
over  in  early  spring  to  destroy  the  eggs  of  the  root-louse,  and 
apliids  on  small  grains  may  sometimes  be  killed  out  on  small 
areas  by  covering  with  straw  and  burning  while  the  plants  are 
small. 

Plowing. — Deep  plowing  and  thorough  harrowing  are  the  most 
effective  means  of  ridding  the  soil  of  many  pests  of  staple  crops. 

Late  Fall  Plowing. — Where  the  succession  of  crops  permits, 
plowing  in  the  late  fall  is  most  advantageous,  as  it  destroys  the 
insects  while  hibernating,  although  for  some  insects  early  fall 
plowing  and  thorough  harrowing  during  the  fall  are  preferable. 
Where  plowing  is  not  possible,  thorough  disking  is  often  used 
for  the  same  purpose,  as  on  alfalfa.  As  different  insects  pass  the 
winter  in  different  stages  this  method  does  not  affect  all  alike. 
Some  will  be  destroyed  by  having  the  cells  into  which  they  have 
gone  to  pass  the  winter  broken  up,  and  being  unable  to  construct 
new  cells  they  will  be  subjected  to  undue  freezing  and  thawing 
and  excessive  moisture,  and  will  thus  be  killed  by  the  weather. 
Cutworms  and  the  corn  stalk-borer  pass  the  winter  in  the  soil 
as  larvae;  the  cotton  boll  worm  or  corn  ear-worm  hibernates 
in  the  pupal  stage;  while  May  beetles  and  click  beetles  hibernate 
as  newly  transformed  beetles;  but  all  of  them  will  be  similarly 
affected  by  the  breaking  up  of  their  winter  cells,  which  is  the 
most  effective  manner  of  combating  them. 

Other  insects  lay  their  eggs  in  the  ground  in  the  fall  and  these 
may  be  buried  too  deep  for  the  young  to  emerge,  or  larvae  or  pupse 
which  normally  remain  near  the  surface  may  be  turned  under  so 
deeply  as  to  destroy  them.  Thus  grasshopper  eggs  are  laid  in 
the  fall  just  beneath  the  surface,  and  by  plowing  in  late  fall  or 
early  spring  they  may  be  turned  under  so  that  but  few  are  able  to 
emerge,  which  is  the  best  means  of  combating  them.  The  apple 
maggot  hibernates  in  the  pupal  stage  just  beneath  the  surface  of 
the  soil,  and  by  deep  plowing  in  early  spring  the  puparia  may  be 
buried  too  deeply  for  the  flies  to  emerge. 

Young  grasshoppers  are  often  destroyed  after  they  hatch  by 
plowing  deep  furrows,  starting  at  the  outside  of  the  field  and  plow- 


36  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

ing  in  a  square,  thus  forcing  them  to  the  centre  and  catching  large 
numbers  of  them  in  the  furrows. 

Early  plowing  and  thorough  harrowing  in  the  spring  are  of 
value  against  cutworms  by  keeping  the  ground  fallow  and  thus 
starving  them  out  before  a  crop  is  planted.  The  same  method 
may  be  used  against  other  pests  with  similar  habits. 

Thorough  cultivation  in  the  summer  has  been  found  to  be  of 
value  against  many  insects,  affecting  them  differently  according  to 
their  habits.  Many  which  pupate  in  the  soil  during  the  summer 
are  destroyed  while  making  their  pupal  cells,  or  these  cells  are 
broken  and  they  are  subjected  to  abnormal  moisture  and  tem- 
perature conditions  and  are  thus  killed.  This  has  been  shown  to  be 
the  case  with  the  cotton  bollworm  or  corn  ear-worm,  and  is  true 
of  the  plum  curculio,  against  which  thorough  cultivation  has 
proved  to  be  one  of  the  most  effective  means  of  control  in  apple 
orchards.  Thorough  cultivation  is  also  of  importance  in  breaking 
up  the  nests  of  ants  which  care  for  such  aphids  as  the  corn  root- 
aphis.  Summer  fallowing  is  used  to  starve  out  some  pests;  for 
example,  the  clover  root-borer  may  be  eradicated  by  plowing  up 
infested  clover  immediately  after  it  is  cut  and  exposing  the  roots 
to  the  sun  and  wind  which  will  soon  dry  them  out  -and  thus  destroy 
the  food  of  the  larvae. 

Trap  Crops. — Trap  crops  are  those  which  are  planted  as  a  bait 
or  lure  to  attract  the  early  insects  so  that  they  may  be  destroyed 
upon  them  before  the  crop  to  be  protected  is  available.  Doubt- 
less the  reason  that  trap  crops  are  not  more  frequently  used  by  the 
farmer  is  because  their  successful  use  requires  more  or  less  of  a 
knowledge  of  the  life  history  and  habits  of  the  pest  to  be  fought. 
But  that  is  easily  acquired  and  will  make  the  jfight  against  them 
more  interesting  and  successful. 

South  of  Mason  and  Dixon's  line  the  harlequin  cabbage 
bug  frequently  becomes  the  most  serious  pest  of  cabbage  and 
related  plants.  When  a  cabbage  patch  has  become  well  infested 
it  is  an  exceedingly  difficult  matter  to  prevent  injury,  for  the  adult 
bugs  cannot  be  killed  by  insecticides  which  will  not  injure  the 
plant.  If,  however,  a  crop  of  kale  be  planted  the  previous  fall 
the  bugs  which  hibernate  over  winter  will  attack  it  in  the  spring, 
and  may  then  be  killed  by  spraying  them  with  pure  kerosene,  and 
the  danger  to  the  cabbage  crop  be  thus  largely  averted. 


FARM  METHODS  P^OR  THE  CONTROL  OF  INSECTS         37 

A  few  rows  of  wheat  are  often  planted  early  in  the  fall  as  a  trap 
for  the  Hessian-fly,  and  as  soon  as  the  eggs  are  deposited  they  are 
plowed  under  deeply  and  the  later  planting  thus  at  least  partly 
protected. 

One  of  the  most  successful  examples  of  averting  injury  by  a 
trap  crop  is  the  use  of  corn  to  lure  the  cotton  boll  worm  and  thus 
prevent  its  injury  to  cotton.  Corn  is  the  favorite  food  plant  of 
this  pest,  which  prefers  to  deposit  its  eggs  on  the  silk  and  tassels. 
By  planting  a  few  strips  of  late-maturing  corn  through  the  cotton 
field,  they  will  come  into  silk  about  the  tune  the  brood  of  moths 
which  normall}^  deposit  their  eggs  on  cotton  are  flying  and  they 
will  lay  them  on  the  corn  in  preference,  which  should  then  be  cut 
and  fed  to  stock.  In  this  way  by  planting  strips  composed  of  sev- 
eral rows  planted  at  successive  dates,  the  cotton  may  be  almost 
entirely  protected.  Possibly  a  modification  of  this  method  may 
be  applied  for  the  protection  of  tomatoes  or  tobacco,  though  these 
crops  have  never  been  thus  protected  from  this  insect  to  our 
knowledge. 

Radishes  are  sometimes  used  as  a  trap  crop  for  the  root-mag- 
gots which  affect  the  roots  of  cabbages  and  onions.  The  same 
principle  is  sometimes  used  in  combating  forest  insects  by  gird- 
ling a  tree  upon  which  certain  kinds  of  forest  pests  will  concentrate, 
and  then  burning  the  tree.  . 

These  examples  will  suffice  to  show  that  very  many  of  the  most 
important  insect  pests  may  be  largely  controlled  by  simply  adapt- 
ing the  general  methods  of  farm  management  so  as  to  avoid  or 
prevent  injury  by  them.  They  indicate  the  importance  of  a 
knowledge  of  the  life  history  of  any  insect  which  is  to  be  combated, 
knowing  which,  some  of  the  above  or  similar  methods  will  often 
suggest  themselves  as  applicable.  Such  a  control  of  insect  life 
through  the  practical  use  of  natm^al  agencies  epitomizes  the  scien- 
tific method  in  the  art  of  agriculture;  i.  e.,  the  most  practical  and 
effective  and  yet  simple  methods  based  upon  exact  knowledge.* 

The  Use  of  Light-Traps. — The  destruction  of  insects  by  at- 
tracting them  to  fights  at  night  has  always  attracted  attention. 
Many  such  devices  have  been  tried  and  several  are  now  on  the 

*  See  F.  M.  Webster,  Farm  Practice  in  the  Control  of  Field  Crop  Insects, 
Yearbook  U.  S.  Dept.  Agr.,  1905,  p.  465,  and  Some  Things  that  the  Grower 
of  Cereal  and  Forage  Crops  Should  Know  about  Insects,  Yearbook  U.  S. 
Dept.  Agr.,  1908,  page  367. 


38       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

market.  Unfortunately,  many  of  the  most  destructive  insects 
are  not  attracted  to  lights.  The  codling  moth  and  corn  earworm, 
for  instance,  are  rarely  seen  at  the  lights.  In  some  cases  where 
injurious  forms  are  flying  to  the  hghts  freely,  for  instance,  when 
June-beetles  are  particularly  abundant,  they  may  be  trapped  by 
this  method  with  some  resulting  benefit.  As  a  rule,  however, 
not  enough  individuals  will  be  killed  to  make  any  noticeable 
difference  in  the  injury  to  the  crops  attacked  and  while  some  in- 
jurious forms  are  being  killed  many  beneficial  ones  will  also  be 
destroyed.  The  method  is  not,  therefore,  commonly  recom- 
mended as  a  practical  means  for  insect  control. 

Mechanical  Means  for  the  Collection  of  Insects. — Some  benefit 
is  realized  from  the  collection  of  insects  by  mechanical  means. 
Of  these  the  most  simple  is  hand-picking.  This  is  practical  on  a 
small  scale  and  is  used  for  the  control  of  tomato  and  tobacco 
horn-worms  and  many  other  insects,  being  used  even  for  the  con- 
trol of  the  Colorado  potato  beetle  in  small  fields.  Grasshoppers 
are  collected  by  the  use  of  hopperdozers  as  described  in  the  dis- 
cussion of  those  insects.  Leaf  hoppers  are  collected  sometimes 
with  machines  of  similar  construction  but  adapted  for  use  with 
row  crops.  Leafhoppers  and  flea-beetles  are  collected  with  some 
success  by  the  use  of  shields  covered  with  sticky  material  and 
carried  along  the  rows  of  plants  attached  in  such  position  that 
insects  disturbed  will  be  caught  on  the  sticky  material  when  they 
hop  or  fly  from  the  plants.  Flies  are  trapped  in  large  numbers 
and  trapping  is  one  of  the  best  means  of  control  for  these  insects. 
Mechanical  means  of  collecting  and  killing  insects  are  generally 
less  satisfactory  than  the  use  of  spra3^s  when  the  latter  are  avail- 
able for  the  control  of  the  insects  but  serve  a  useful  purpose  for 
some  forms  which  can  not  readily  be  controlled   by  spraying. 


CHAPTER  V 
INSECTICIDES 

Materials  used  for  the  destruction  of  insects  are  commonly 
called  insecticides,  and  are  roughty  divisible  into  four  classes: 

1.  Poisons,  which  kill  by  being  eaten  and  are  usuall}^  composed 
of  various  forms  of  arsenic  and  are  therefore  often  called  arseni- 
cals.     They  are  frequently  called  the  stomach  poisons. 

2.  Contact  insecticides,  which  kill  by  either  clogging  up  the 
spiracles,  the  openings  of  the  respiratory  system,  or  by  entering 
the  trachea,  and  thus  causing  suffocation,  or  by  their  corrosive 
action  on  the  skin. 

3.  Repellants,  which  deter  the  insect  from  attacking  the  plant 
or  animal  to  which  they  are  applied. 

4.  Gases,  which  are  used  for  fumigating  buildings,  stored  prod- 
ucts and  greenhouses  where  other  means  are  not  practicable. 

1.  Poisons 

Poisons  are  applied  to  the  food  of  the  insect  and  must  be  eaten 
by  it  to  be  effective.  It  is  evident,  therefore,  that  they  are  only 
effective  against  biting  (mandibulate)  insects,  or  for  those  which 
lap  up  their  food  from  the  surface,  and  that  they  are  of  no  avail 
against  the  true  sucking  insects,  such  as  the  true  bugs,  which  suck 
the  juices  from  beneath  the  surface  of  the  plant.  Poisons  are  not 
always,  however,  the  most  effective  means  of  combating  biting 
insects,  which  are  sometimes  more  effectively  controlled  by  con- 
tact insecticides  or  other  means. 

Nearly  all  of  the  stomach  poisons  are  derivatives  of  arsenic 
and  are  therefore  termed  arsenicals.  As  they  are  dangerous  to 
human  life  they  should  be  kept  well  labeled,  locked  up  when  not 
in  use,  and  vessels  in  which  they  have  been  used  should  be  care- 
fully cleaned. 

1.  Paris  green  is  a  green  crystalline  powder  composed  of  the 
aceto-arsenite  of  copper.     When  properly  made  it  should  contain 

39 


40  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

at  least  50  per  cent  arsenic  oxid  (AS2O5),  and  there  should  be  as 
little  water-soluble  arsenic  as  possible,  for  the  water-soluble  arsenic 
is  the  cause  of  the  burning  of  foliage  which  often  results  from  the 
use  of  Paris  green.  Various  state  laws  require  that  there  be  not 
over  31  per  cent  soluble  arsenic,  but  even  this  amount  is  often 
injurious  to  tender  foliage.  Paris  green  is  a  rather  coarse  powder 
and  settles  readily  in  water,  and  is  readily  washed  off  by  drenching 
rains.  It  costs  from  35  to  50  cents  per  pound.  It  is  usually  used 
at  a  rate  of  from  3  to  8  ounces  to  a  50-gallon  barrel  of  water;  5 
ounces  per  barrel  is  satisfactory  for  most  purposes.  In  mixing, 
first  stir  up  in  a  small  vessel  with  a  little  water  into  a  paste,  which 
will  mix  more  readily.  Add  an  equal  weight  of  quicklime,  or 
slightly  more  will  do  no  harm,  which  will  take  up  any  soluble 
arsenic. 

2.  London  purple  is  a  waste  product  in  the  manufacture  of 
aniline  dyes,  and  is  principally  arsenic  and  lime.  It  is  quite 
variable  in  composition  and  usually  contains  a  much  higher, 
and  quite  variable,  amount  of  soluble  arsenic,  so  that  it  is  apt  to 
scald  the  foliage  unless  thoroughly  mixed  with  fresh  stone  lime. 
For  this  reason  it  is  now  used  only  for  rough  work,  such  as  poison- 
ing grasshoppers,  making  poisoned  bran  mash,  etc.,  and  is  not 
to  be  recommended  for  general  use  on  fruit  trees  and  garden 
crops.  It  usually  costs  10  or  12  cents  a  pound,  and  is  used  in 
the  same  proportions  and  in  the  same  way  as  Paris  green. 

3.  Arsenate  of  lead  is  sold  in  the  form  of  a  white  paste  con- 
taining about  50  per  cent  water  and  also  as  a  dry  white  powder. 
Standards  of  purity  for  this  material  require  that  the  paste  con- 
tain not  moi'e  than  50  per  cent  water  and  not  more  than  f  per 
cent  water-soluble  arsenic  oxide,  while  there  must  be  not  less 
than  121  per  cent  total  arsenic  oxide.  The  dry  powder  will  lack 
the  water  and  contain  a  correspondingly  larger  percentage  of 
other  ingredients.  Since  this  material  contains  a  relatively  small 
amount  of  soluble  arsenic  it  may  be  used  at  a  greater  strength  than 
the  other  arsenicals  without  injuring  foliage  of  plants  which  are 
susceptible  to  injury  from  the  other  arsenicals.  From  one  to  eight 
pounds,  paste  form,  are  used  to  the  50  gallon  barrel  of  water,  2  or 
3  pounds  being  most  commonly  recommended  for  the  majority  of 
the  pests  of  orchard  and  garden.  Arsenate  of  lead  remains  in 
suspension  well,  much  better  than  Paris  green,  and  is  very  ad- 


INSECTICIDES  41 

hesive,  remaining  on  foliage  for  several  weeks.  It  is  made  from 
arsenate  of  soda  and  acetate  of  lead  and  may  readily  be  prepared 
by  the  user.  This  is  not  recommended  on  account  of  the  vari- 
ability in  the  purity  of  the  constituent  chemicals  and  the  incon- 
siderable saving  effected  by  the  home  preparation. 

Commercial  arsenate  of  lead  may  be  purchased  at  prices 
ranging  from  10  to  30  cents  per  pound  for  the  paste  and  from  25 
to  50  cents  for  the  powder. 

Powdered  arsenate  of  lead  was  prepared  first  rather  for  use  as 
a  dust  than  for  spraying  purposes.  Perfection  of  the  process  of 
manufacture  of  the  dust  has  given  a  product  that  is  as  cheap  and 
in  every  way  as  satisfactory  as  the  paste.  For  this  reason  users 
are  more  and  more  coming  to  prefer  the  powder.  It  mixes  more 
readily  with  water,  remains  in  suspension  just  as  well  and,  being 
of  only  one-half  the  weight  of  the  paste,  effects  a  considerable 
saving  in  transportation. 

The  powder  also  eliminates  one  source  of  loss  to  which  the 
paste  is  Hable,  that  is,  drying  out.  Paste  arsenate  of  lead  that 
has  dried  is  practically  wasted  as  it  is  almost  impossible  to  get  it 
thoroughly  mixed  with  water.  The  dust  will  keep  indefinitely 
if  it  is  stored  in  a  dry  place.  Arsenate  of  lead  in  the  dry  form  is 
the  only  arsenical  used  to  any  extent  in  orchard  dusting. 

It  is  well  for  the  student  to  remember  that  spraying  formulas 
calling  for  arsenate  of  lead  usually  mean  the  arsenate  in  paste  form 
if  the  powder  is  not  definitely  specified.  This  is  because  the 
paste  was  first  used  and  formulas  were  established  on  that  basis. 

Arsenate  of  lead  is  the  most  valuable  and  widely  used  of  all 
the  insecticides  used  as  stomach  poisons,  having  long  since  dis- 
placed Paris  green  which  was  formerly  the  leading  arsenical. 

4.  Arsenite  of  lead  is  a  compound  very  similar  to  the  arsenate 
but  less  effective  and  contains  more  soluble  arsenic  and  so  is  more 
likely  to  burn  foliage.  It  is  made  from  sodium  arsenite  and  a 
lead  compound  but  is  rarely  used  and  not  to  be  recommended. 

5.  Arsenite  of  lime  is  a  home-made  arsenical,  very  much  cheaper 
than  those  previously  mentioned,  which  gives  very  satisfactory 
results  for  certain  purposes.  It  is  not  as  adhesive  as  arsenate 
of  lead,  and  as  it  sometimes  burns  foliage  has  been  largely  dis- 
carded for  orchard  spraying.  It  is,  however,  very  satisfactory 
for  potatoes  and  other  low-growing  crops,  especially  when  added 


42  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

to  bordeaux  mixture,  which  sticks  it  to  the  foHage,  and  it  may  be 
used  to  good  advantage  for  fighting  grasshoppers  and  leaf-eating 
caterpillars  when  it  is  desired  to  poison  considerable  areas  of 
weeds  or  waste  grass.  The  so-called  Kedzie  formula  (See  Sodium 
arsenite  below)  is  the  most  satisfactory,  as  the  soda  hastens 
the  complete  combination  of  the  arsenic,  and  the  resulting 
solution  is  in  a  clear  liquid  form  which  can  be  readily  measured.* 
6.  Arsenate  of  calcium,  sometimes  called  arsenate  of  lime,  is 
an  insecticide  of  more  recent  application  and  is  perhaps  the  best 
substitute  for  arsenate  of  lead.  It  has  several  points  in  its  favor 
over  the  lead  compound,  being  cheaper  under  normal  conditions, 
and  possessing  greater  killing  power,  pound  for  pound,  since  a 
pound  of  the  calcium  arsenate  has  a  greater  percentage  of  arsenic 
than  does  a  pound  of  lead  arsenate.  It  is  somewhat  more  liable 
to  scorch  foliage  than  is  the  lead  arsenate  and  it  is  recommended 
that  it  be  always  used  with  some  stone  lime  added.  It  is  not  a 
safe  material,  according  to  latest  reports,  to  use  on  peach  foliage. 
Calcium  arsenate  is  marketed  as  a  paste  and  also  in  the  dust  form. 
It  has  been  used  as  a  substitute  for  lead  arsenate  in  dusting  work 
It  may  be  prepared  at  home  but  the  same  objections  are  to  be 
raised  as  against  the  home  manufacture  of  lead  arsenate.  The 
formula  and  directions  follow: 

Stone  lime,  best  grade 2  lbs. 

Sodium  arsenate,  fused  (65%  As20s) 4  lbs. 

Water 1  gallon. 

Dissolve  the  sodium  arsenate  in  a  little  hot  water.  Place  the 
stone  lime  in  a  wooden  tub  or  bucket  and  add  just  enough  water 
to  start  slaking.  Then  add  the  dissolved  sodium  arsenate.  Stir 
constantl}^  and  add  small  amounts  of  water  from  time  to  time 
until  the  slaking  has  ceased.  Allow  the  solids  to  settle  and  pour 
off  the  clear  liquid  above.  The  resulting  paste  is  calcium  arsenate 
and  may  be  used  at  from  one  to  three  pounds  per  barrel  of  water. 
Impurities  in  the  materials  used  may  reduce  the  killing  power  of 

*  Arsenite  of  lime  is  often  made  by  boiling  1  pound  of  lime  with  2  pounds 
of  white  arsenic  in  1  gallon  of  water  for  thirty  to  forty-five  minutes.  This 
results  in  a  paste  of  arsenite  of  lime,  which  settles  in  the  solution.  One  quart 
of  this  mixture  is  used  per  barrel  of  water  or  Bordeaux  mixture,  but  unless 
the  stock  solution  is  always  stirred  equally  well,  the  amount  of  poison  in  a 
quart  will  be  quite  variable,  with  varying  effectiveness;  hence  the  clear  solu- 
tion of  arsenite  of  soda  as  in  the  Kedzie  formula  is  preferable. 


INSECTICIDES  43 

the  material  or  increase  the  danger  of  burning  foliage  so  that  it  is 
generally  wiser  to  use  the  commercial  product. 

7.  Arsenite  of  zinc  is  another  material  which  is  occasionally 
used  as  a  substitute  for  lead  arsenate.  It  comes  in  the  commercial 
form  as  a  rather  light  powder.  It  has  a  tendency  to  burn  foliage 
but  has  good  killing  qualities.  It  may  be  used,  if  conditions  de- 
mand, with  a  fair  degree  of  safety  by  combining  it  with  bordeaux 
mixture  or  with  hme.  It  should  not  be  used  at  more  than  half 
the  strength  recommended  for  arsenate  of  lead. 

8.  White  arsenic  is  the  basis  for  all  the  stomach  poisons,  at 
least  indirectly.  It  is  cheap  and  a  violent  poison  to  insects  but 
on  account  of  its  complete  solubility  is  not  available  as  a  spray 
material.  It  is  of  value  for  use  in  poisoned  baits  and  as  a  basis 
for  the  preparation  of  other  materials. 

9.  Sodium  arsenite  is  a  cheap  and  effective  insecticide,  avail- 
able for  some  uses.  It  is  generally  prepared  by  the  user,  the  com- 
mon Kedzie  formula  following: 

White  arsenic 1  lb. 

Sal  soda 2  lbs. 

Water 1  gal. 

Mix  the  arsenic  into  a  paste  with  a  little  water  and  dissolve 
the  sal  soda  in  the  remaining  water.  Add  the  arsenic  paste  to  the 
soda  solution  and  boil  until  the  arsenic  is  completely  dissolved. 
Add  water  to  make  a  full  gallon  and  use  at  the  rate  of  one  quart  to 
fifty  gallons  of  bordeaux  mixture,  being  careful  to  see  that  the 
bordeaux  has  an  excess  of  lime.  This  material  is  not  widely 
used  although  in  some  regions  it  is  the  favorite  spray  for  potatoes. 

10.  Hellebore. — The  powdered  roots  of  the  white  hellebore  are 
often  used  as  an  insecticide  in  place  of  arsenicals,  especially  for 
currant  worms,  rose  slugs,  and  similar  saw-fly  larvsB  and  for  insects 
affecting  crops  soon  to  be  eaten,  as  the  ..hellebore  is  much  less 
poisonous  to  man  and  animals  than  arsenicals.  It  may  be  applied 
dry,  diluted  with  from  5  to  10  parts  of  flour,  or  as  a  spray,  1  ounce 
to  a  gallon  of  water.  It  is  too  expensive  to  use  except  for  a  few 
plants  in  the  yard  or  garden,  and  lUve  pyrethrum,  deteriorates 
with  age  and  if  exposed  to  the  air. 

Harmlessness  of  Arsenicals  when  Properly  Applied. — The  ques- 
tion is  frequently  asked  whether  it  is  safe  to  apply  arsenicals  to 
vegetables  and  fruits  to  be  used  as  food.  Where  sprayed  or  dusted 


44  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

as  directed  the  amount  of  arsenic  which  would  be  deposited  on 
the  plant  would  not  be  sufficient  to  cause  any  injury,  and  Professor 
C.  P.  Gillette  has  shown  that  twenty-eight  cabbages  dusted  in  the 
ordinary  way  would  have  to  be  eaten  at  one  meal  in  order  to  pro- 
duce poisonous  effects.  Occasionally  growers  dust  cabbage  with 
an  unreasonable  amount  of  poison,  and  very  rarely  instances  of 
poisoning  are  recorded,  but  there  is  no  value  in  applying  any  more 
poison  than  is  necessary  to  make  a  thin  film  over  the  surface,  and 
more  than  that  is  wasted.  Because  a  certain  amount  of  poison 
will  kill  an  insect  does  not  indicate  that  a  larger  amount  can  kill 
it  any  "  deader."  Experiments  have  also  shown  that  tobacco 
sprayed  as  recommended  cannot  possibly  bear  enough  arsenic  to 
be  injurious,  and  that  cattle  or  horses  may  be  pastured  under 
trees  sprayed  with  arsenicals  with  impunity.* 

2.  Contact  Insecticides 

Contact  insecticides  are  used  against  insects  with  sucking 
mouth-parts  and  soft-bodied  biting  insects  which  may  be  more 
readily  destroyed  by  this  means  than  by  arsenicals.  These  sub- 
stances are  fatal  to  the  insect  either  by  clogging  the  spiracles 
or  trachea,  and  thus  causing  suffocation,  or  by  corroding  the 
skin.  It  should  be  remembered  that  the  chitinous  skin  of  most 
insects  is  not  easily  corroded,  and  that  in  most  cases  a  material 
strong  enough  to  penetrate  the  skin  will  also  injure  foliage,  so  that 
only  soft-bodied  insects  can  be  combated  with  corrosive  sub- 
stances upon  foliage. 

In  the  application  of  contact  insecticides  it  is  absolutely  essen- 
tial that  the  spray  come  into  contact  with  the  insect,  as  a  mere  spray- 
ing of  the  foliage  is  of  no  value  whatever. 

1.  Kerosene  emulsion  is  one  of  the  oldest  remedies  for  plant- 
lice  and  other  sucking  and  soft-bodied  insects,  and  is  often 
resorted  to  because  it  is  readily  made  and  the  materials  are 
always  at  hand. 

Dissolve  I  pound  of  hard  or  whale-oil  soap  (or  1  quart  soft 
soap)  in  1  gallon  of  boiUng  water.   Add  2  gallons  of  kerosene  and 

*  This  is  not  true  of  grass  beneath  trees  which  have  been  sprayed  with 
a  straight-jet  fire-hose,  as  is  commonly  done  in  Massachusetts  in  the  extensive 
operations  against  the  gypsy  moth,  but  refers  to  spraying  which  has  been 
done  with  an  ordinary  spray  nozzle,  which  applies  the  material  as  a  fine  spray. 


INSECTICIDES  45 

churn  with  a  force  pump  by  pumping  back  and  forth  for  five  to 
ten  minutes  until  the  oil  is  thoroughly  emulsified,  forming  a 
creamy  mass  with  no  drops  of  free  oil  visible.  This  stock  solution 
is  now  diluted  so  that  the  resulting  mixture  will  contain  the  de- 
sired per  cent  of  kerosene.  Thus  for  aphids  one  part  of  the  stock 
solution  should  be  diluted  with  from  10  to  15  parts  of  water,  giving 
from  4  to  6  per  cent  of  kerosene  in  the  spray,  while  for  a  winter 
wash  for  San  Jose  scale,  it  should  be  diluted  only  three  or  four 
times,  giving  from  16  to  22  per  cent  kerosene.  The  emulsion  must 
be  thoroughly  churned  and  should  be  applied  with  a  nozzle  throw- 
ing a  fine  spray.  Apply  only  enough  to  wet  the  insects.  Equally 
effective  emulsions  may  be  made  from  crude  petroleum,  the  pro- 
portion of  the  soap  and  crude  oil  in  the  stock  emulsion  varying 
with  the  quality  of  the  oil.  Emulsions  made  with  some  of  the 
crude  oils  seem  to  be  much  less  injurious  to  foliage  of  some  plants 
than  when  made  with  kerosene.  Such  an  emulsion  is  made  in 
California  from  distillate  oils  and  is  known  as  distillate  emulsion. 
We  have  used  crude  Texas  oils  with  equal  success. 

2.  Kerosene. — Pure  kerosene  should  never  be  used  on  foliage,  for 
though  occasionally  someone  will  report  using  it  successfully 
without  injury,  in  practically  all  cases  serious  burning  of  the  fohage 
results.  It  was  formerly  recommended  against  the  San  Jose 
scale  on  fruit  trees,  but  such  serious  injury  resulted  that  it  has  been 
almost  entirely  discarded,  though  it  may  be  used  on  apple  and  pear 
trees  if  applied  with  a  nozzle  which  throws  a  fine  spray,  on  a  bright 
sunny  day,  and  only  a  very  thin  film  applied  to  the  tree  while  it  is 
dormant,  but  even  these  trees  are  often  injured  if  the  application 
is  not  made  with  the  greatest  care. 

3.  Crude  Petroleum. — Crude  petroleum  is  used  in  the  same  man- 
ner as  kerosene  against  scale  insects,  but  seems  to  be  less  injurious 
to  the  tree,  and  has  been  extensively  used  in  New  Jersey  against 
the  scale  on  peaches,  where  but  little  injury  has  resulted  where  it 
has  been  carefully  applied.  It  contains  more  heavy  oils  and  con- 
sequently does  not  penetrate  the  bark  so  readily,  and  the  hght  oils 
evaporating  leave  the  heavy  oils  on  the  bark  for  some  months, 
which  aids  in  preventing  young  scales  from  getting  a  foothold. 
Crude  oil  for  use  as  an  insecticide  should  have  a  specific  gravity  of 
from  43°  to  45°  Beaume  scale,  and  is  sold  by  certain  Eastern  com- 
panies as  "  insecticide  oil." 


46  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

4.  Miscible  Oils. — During  the  last  few  years  several  manufac- 
turers have  placed  on  the  market  under  various  trade  names  what 
are  now  called  miscible  oils.  These  are  petroleum  rendered  solu- 
ble by  the  addition  of  vegetable  oils,  cut  or  saponified  with  an 
allcali,  and  are  really  a  sort  of  liquid  petroleum  soap  which  will 
combine  readily  with  water.  They  have  been  used  principally 
as  winter  washes  against  the  San  Jose  scale,  for  which  thej'  are 
most  effective  when  diluted  10  or  12  times.  For  a  summer  wash 
they  have  been  used  effectively  against  plant-lice  and  other  insects 
for  which  kerosene  emulsion  would  be  used,  diluted  25  to  30  times. 
In  barrel  lots  the  miscible  oils  sell  at  40  to  50  cents  per  gallon,  thus 
making  the  cost  of  a  gallon  of  mixture  for  a  winter  application  at 
10  per  cent,  4  or  5  cents  per  gallon. 

5.  Whale-oil  and  Other  Soaps. — Any  good  soap  is  an  effective 
insecticide  for  destroying  aphides  and  young  or  soft-bodied  larvae. 
Any  good  laundry  soap  made  into  a  thick  solution  one-half  pound 
per  gallon  is  an  excellent  remedy  for  such  insects  on  house- 
plants.  Whale-oil  or  fish-oil  soap  has  been  extensively  used 
against  scale  insects  and  plant-lice.  The  best  brands  are  made 
from  caustic  potash  rather  than  caustic  soda,  and  should  contain 
not  over  30  per  cent  of  water,  there  being  wide  variation  in  the 
water  content.  For  the  pea  aphis  and  other  aphids  1  pound 
to  6  gallons  of  water  has  been  found  very  effective.  For  a  win- 
ter wash  for  the  San  Jose  scale  2  pounds  per  gallon  of  water  are 
applied  while  hot,  the  soap  being  dissolved  in  hot  water.  The 
soap  can  be  bought  for  3|  to  4  cents  a  pound  in  large  quantities, 
thus  making  the  treatment  for  scale  cost  from  7  to  8  cents  a 
gallon. 

6.  Lime-sulfur  Wash. — The  lime-sulfur  wash  has  long  been 
the  standard  remedy  for  the  San  Jose  scale  on  the  Pacific  Coast, 
and  during  the  last  15  years  has  come  into  wide  use  in  the  East 
for  the  same  pest.  It  has  also  been  found  to  be  an  efficient 
remedy  for  the  pear  leaf  blister-mite  and  the  oyster-shell  bark- 
louse.  In  addition  to  its  insecticidal  properties  it  is  an  excellent 
fungicide,  and  the  spring  applications  just  before  the  buds  start 
are  very  effective  in  killing  out  the  wintering  spores  of  various 
fungous  diseases,  while  the  diluted  wash  is  being  used  as  a  summer 
spray  for  fungous  diseases  in  place  of  bordeaux  mixture. 


INSECTICIDES  47 

The  usual  formula  is,  unslaked  stone  lime,  20  pounds;  flowers 
(or  flour)  of  sulfur,  15  pounds,  water  to  make  50  gallons.  Stir 
up  enough  water  with  the  sulfur  to  make  a  thick  paste.  Slake 
the  hme  in  the  vessel  in  which  it  is  to  be  cooked  with  a  small 
quantity  of  hot  water.  Then  add  the  sulfur  paste  to  the  slaking 
lime.  Add  10  or  15  gallons  of  water  and  boil  for  forty-five  min- 
utes. The  mikture  may  then  be  diluted  to  make  a  barrel  of  45  or 
50  gallons,  straining  it  carefully  into  the  spray  barrel  or  tank.  A 
large  iron  kettle  or  hog-scalder  may  be  used  for  boiling  the  wash, 
or  where  steam  can  be  made  available  a  steam  pipe  may  be  run 
into  several  barrels  and  the  wash  boiled  in  them.  Such 
barrels  may  well  be  placed  upon  a  platform  so  that  the  wash 
may  be  drawn  from  them  directly  into  the  spray-tank.  The 
materials  for  making  the  wash  will  cost  1|  to  1|  cents  per  gallon 
and  the  labor  practically  as  much  more.  The  leading  manufac- 
turers and  dealers  in  insecticides  are  now  selling  concentrated 
lime-sulfur  solution  which  is  all  ready  for  use  by  merely  diluting 
to  the  desired  strength,  at  a  rate  which  will  make  the  solution 
to  be  used  cost  from  2J  to  3  cents  per  gallon,  nearly  as  cheap 
as  it  can  be  made  at  home  and  with  the  saving  of  time  and  a  dis- 
agreeable job.  In  some  communities  a  central  plant  makes  the 
wash  and  can  sell  it  with  a  fair  profit  at  a  low  rate. 

7.  Home-made  Concentrated  Lime-sulfur. — During  the  last  few 
seasons  many  large  growers  have  been  making  their  own  con- 
centrated lime-sulfur  solution,  and  where  the  quantity  to  be 
used  warrants,  a  considerable  saving  may  be  effected.  The  New 
York  Agricultural  Experiment  Station  has  made  very  careful 
studies*  of  the  best  methods  of  making  and  diluting  the  mixture 
from  which  the  following  is  quoted : 

Geneva  Station  Formula  for  Concentrated  Lime-sulfur  Solution. 

fPure  CaO 36  lbs. 

Lime     \  If  95  per  cent  pure .' 38  lbs. 

[If  90  per  cent  pure 40  lbs. 

Sulfur,  high  grade,  finely  divided 80  lbs. 

Water 50  gals 

*Bulletins  329  and  330  N.  Y.  (Geneva)  Agricultural  Experiment  Station 


48 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


DiLaTioNS  FOR  Dormant  and  Summer  Spraying  with  Lime-sulphur 

Mixtures. 


Amount  of  Dilution.     Number  of  Gallons  of  Water  to  One 
Gallon  of  Lime-sulfur  Solution. 

hydrometer. 

For  San  Jose  Scale. 

For  Blister-mite. 

For  Summer  Spray- 
ing of  Apples. 

Degrees  Beaume 

36 

9 

8M 

8 

7^ 

7M 

6M 

6K 

6 

5H 

5 

4M 

SH 

3^ 
3M 
3 

2M 
2^ 

2 

12J^ 
12 

UK 
11 

101^ 
10 

9M 

9 

8H 

8 
7K 

7 

6H 
6 

5K 
5 

4M 
4 

3M 
3M 
3 

45 

35 

43  M 

34 

41M 

33 

40 

32 

37% 

31 

36M 

30 

3414 

29 

32% 

28 

31 

27 

29^ 

26 

27% 

25 

26 

24 

24% 

23 

22% 

22 

21% 

21 

19% 

20 

18% 

19.- 

17 

18 

16 

17 

15 

16 

14 

15 

12% 

"  In  making,  slake  the  lime  in  about  10  gallons  of  hot  water, 
adding  the  Imiips  of  lime  gradually  to  avoid  too  violent  boihng  and 
spilling  over.  .  .  .  The  sulfur  must  be  thoroughly  moistened 
and  made  into  an  even,  fluid  paste  without  lumps  (before  adding  to 
the  lime) ....  Pour  in  the  sulfur  paste  gradually  during  the 
slaking,  stirring  constantly  to  prevent  the  formation  of  lumps, 
and  when  the  slaking  has  finished  add  the  full  amount  of  water 
and  boil  gently  for  one  hour.  If  kettles  and  fire  are  used,  more 
than  the  required  amount  of  water  may  be  used  at  first,  to  com- 
pensate for  evaporation,  or  the  volume  may  be  kept  constant  by 
adding  successive  small  quantities  to  hold  the  mixture  at  the 
original  level,  as  shown  by  a  notch  on  a  stick  resting  on  the  bot- 
tom of  the  kettle,  and  marked  when  the  mixture  first  begins  to 
boil.  When  boihng  with  live  steam  the  mixture  will  be  more 
likely  to  increase  in  volume  than  to  decrease,  so  that  no  water 
need  be  added. 


INSECTICIDES  49 

"  This  concentrate  will  keep  with  little  change,  unless  the 
weather  is  below  5°  F.,  if  stored  in  filled,  stoppered  barrels. 
Even  in  open  receptacles  there  will  be  no  loss  if  the  surface  be 
covered  by  a  layer  of  oil  to  prevent  access  of  air.  Each  boiHng 
should  be  tested  with  a  Beaume  hydrometer*  and  its  density 
marked  on  the  barrels  or  other  containers." 

The  dilution  is  based  upon  the  specific  gravity  as  shown  by 
the  hydrometer  and  may  be  safety  made  according  to  the  out- 
line in  the  above  table. 

In  making  this  mixture  it  is  important  that  onty  high-grade, 
pure  hme  should  be  used,  and  hme  with  less  than  90  per  cent 
calcium  oxid  (CaO)  should  be  discarded. 

8.  Self-boiled  Lime-sulfur. — Self-boiled  lime-sulfur  has  proven 
to  be  the  only  safe  fungicide  for  the  foliage  diseases  of  the 
peach  and  stone  fruits,  and  is  used  extensively  as  a  summer  spray 
on  pome  fruits.  As  a  winter  wash  for  San  Jose  scale  it  has  not 
proven  effective,  but  when  used  as  a  summer  spray  for  fungous 
diseases  it  has  some  considerable  insecticidal  value.  This  mixture 
has  been  developed  chiefly  by  the  work  of  Mr.  W.  M.  Scott 
formerly  of  the  United  States  Department  of  Agriculture,  from 
whose  latest  bulletin t  the  following  is  quoted: 

"  In  order  to  secure  the  best  action  from  the  lime,  the  mix- 
ture should  be  prepared  in  rather  large  quantities,  at  least  enough 
for  200  gallons  of  spray,  using  32  pounds  of  lime  and  32  pounds 
of  sulfur.  The  lime  should  be  placed  in  a  barrel  and  enough  water 
(about  6  gallons)  poured  on  to  almost  cover  it.  As  soon  as  the 
lime  begins  to  slake  the  sulfur  should  be  added,  after  first  running 
it  through  a  sieve  to  break  up  the  lumps,  if  any  are  present. 
The  mixture  should  be  constantly  stirred  and  more  water  (3  or 
4  gallons)  added  as  needed  to  form  at  first  a  thick  paste  and  then 
gradually  a  thin  paste.  The  hme  will  supply  enough  heat  to 
boil  the  mixture  several  minutes.  As  soon  as  it  is  well  slaked 
water  should  be  added  to  cool  the  mixture  and  prevent  further 
cooking.  It  is  then  ready  to  be  strained  into  the  spray  tank, 
diluted,  and  applied. . 

"  The  stage  at  which  cold  water  should  be  poured  on  to  stop 

*  These  hydrometers,  made  specially  for  testing  lime-sulfur  mixture,  may 
be  obtained  from  the  Bausch  &  Lomb  Optical  Co.,  Rochester,  N.  Y.,  and 
other  dealers  in  laboratory  glassware. 

t  Farmers'  Bulletin,  440,  U.  S.  Dept.  of  Agr.,  p.  34. 


50  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

the  cooking  varies  with  different  Hmes.  Some  Hmes  are  so  shiggish 
in  slaking  that  it  is  difficult  to  obtain  enough  heat  from  them  to 
cook  the  mixture  at  all,  while  other  limes  become  intensely  hot 
on  slaking,  and  care  must  ])e  taken  not  to  allow  the  boiling  to 
proceed  too  far.  If  the  mixture  is  allowed  to  remain  hot  for 
fifteen  or  twenty  minutes  after  the  slaking  is  completed,  the  sulfur 
gradually  goes  into  solution,  combining  with  the  lime  to  form 
sulfides,  which  are  injurious  to  peach  foliage.  It  is  therefore 
very  important,  especially  with  hot  lime,  to  cool  the  mixture 
quickly  by  adding  a  few  buckets  of  water  as  soon  as  the  lumps 
of  lime  have  slaked  down.  The  intense  heat,  violent  boiling, 
and  constant  stirring  result  in  a  uniform  mixture  of  finely  divided 
sulfur  and  lime,  with  only  a  very  small  percentage  of  the  sulfur 
in  solution.  It  should  be  strained  to  take  out  the  coarse  particles 
of  lime,  but  the  sulfur  should  be  carefully  worked  through  the 
strainer." 

Its  most  important  use  is  as  a  carrier  for  the  arsenical,  usually 
arsenate  of  lead,  used  in  spraying  peach  trees  and  other  plants 
with  tender  foliage. 

9.  Sulfur. — Pure  sulfur  is  one  of  the  best  remedies  for  red 
spider,  on  whatever  plants  it  may  occur,  and  for  other  mites  which 
infest  citrus  fruits.  It  may  be  dusted  on  the  infested  plants  or  trees 
or  applied  with  any  other  insecticide,  using  1  or  2  pounds  to  50 
gallons.  For  citrus-mites  the  lye-sulfur  wash  and  sulfide  of  hme 
are  extensively  used.  Sulfur  is  frequently  dusted  in  poultry 
houses  to  rid  them  of  lice,  and  may  be  mixed  with  lard  and  rubbed 
on  the  skin  of  domestic  animals  affected  with  lice. 

10.  Pyrethrum,  buhach,  or  Persian  insect  powder,  is  made  by 
pulverizing  the  petals  of  the  pyrethrum  blossom,  and  kills  insects 
by  clogging  their  breathing  pores.  It  is  not  poisonous  to  man  or 
domestic  animals  and  may  therefore  be  used  where  other  insecti- 
cides would  be  objectionable.  It  is  chiefly  used  for  household 
pests,  and  in  greenhouses  and  small  gardens.  It  deteriorates 
rapidly  with  age  and  should  be  kept  in  tight  cans.  An  objection 
to  much  commonly  bought  is  that  it  has  been  kept  in  stock  too 
long  by  the  retailer,  thus  losing  its  strength.  Large  users  buy 
direct  from  the  only  American  manufacturers,  the  Buhach  Pro- 
ducing Co.,  Stockton,  Cal.  It  may  be  used  as  a  dry  powder, 
pure  or  diluted  with  flour,  or  in  water  at  the  rate  of  1  ounce  to  2 


INSECTICIDES  51 

gallons,  which  should  stand  a  day  before  using.  For  immediate 
use  it  should  be  boiled  in  water  for  five  or  ten  minutes.  It  is  fre- 
quently burnt  in  rooms  to  destroy  mosquitoes  and  flies,  for  which 
it  is  effective,  without  leaving  any  odor  after  the  room  is  aired.* 

11.  Tobacco. — A  tobacco  decoction  may  be  made  by  boiling  or 
steeping  tobacco  leaves,  stems,  and  refuse  in  water  at  the  rate  of 
1  pound  to  1  or  2  gallons.  This  may  be  diluted  slightly  according 
to  the  strength  of  the  tobacco  and  the  insect  to  be  combated. 
Such  a  decoction  is  an  excellent  remedy  for  dipping  plants  affected 
with  aphids,  and  may  be  used  as  a  spray  for  plant-lice  and  similar 
soft-bodied  insects.  Various  extracts  and  solutions  of  tobacco  are 
now  sold  by  manufacturers  which  are  extensively  used  in  spraying 
against  plant-lice,  and  which  are  proving  more  satisfactory  on 
account  of  their  uniform  strength.  Tobacco  dust  has  been  used 
successfully  against  root-infesting  aphids  by  removing  the  sur- 
face soil  and  applying  a  liberal  dressing  of  the  dust  and  then 
covering.  The  rains  leaching  through  the  tobacco  carry  the 
tobacco  water  to  the  affected  roots  and  destroy  or  repel  the 
aphids. 

12.  Comynercial  Tobacco  Products  are  much  more  widely  used 
than  home-made  forms  for  the  reason  that  they  are  uniform  in 
their  strength  and  therefore  more  dependable  in  their  action. 
Practically  all  the  commercial  tobacco  extracts  are  produced  by 
one  company,  the  Kentucky  Tobacco  Products  Co.,  of  Louisville, 
Ky.  The  most  widely  used  of  their  products  is  called  ''Black- 
Leaf  40  "  and  is  generally  recommended  as  the  most  satisfactory 
remedy  for  soft-bodied  sucking  insects  which  require  treatment 
during  the  growing  season  of  the  plant.  "  Nicofume,'^  another 
of  their  products,  differs  from  the  "  Black-Leaf  40  "  in  that  it  con- 
tains nicotine  in  volatile  form  and  is  therefore  useful  as  a  fumigant 
as  well  as  for  spraying.  Its  greatest  value  is  in  the  greenhouse. 
It  will  be  found  satisfactory  usually  to  use  these  materials  a  little 
stronger  than  is  recommended  by  the  company,  otherwise  the 
directions  accompanying  the  material  will  apply. 

13.  Soaps  of  many  kinds  are  efficient  insecticides.  They  are 
used  as  a  substitute  for  kerosene  emulsion  and  tobacco  extracts 
to  combat  aphids  and  other  insects,  especially  on  house  plants  and 
in  greenhouses.     Various  soaps  are  especially  prepared  to  be  used 

*  See  Farmers'  Bulletin,  444,  U.  S.  Dept.  Agr.,  p.  7. 


52  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

as  insecticides  and  many  of  these  have  value.  Whale-oil  or  fish- 
oil  soap  is  more  widely  used  as  an  insecticide  than  other  kinds.  It 
may  be  prepared  at  home,  using  about  twenty  pounds  of  the  oil, 
which  should  be  saponified  by  stirring  into  it  a  solution  of  5  to  6 
pounds  caustic  soda  in  a  half-gallon  of  water.  These  soaps  may 
be  found  on  the  market,  ready  for  use  and  in  normal  times  are 
fairly  cheap.  They  are  widely  used  in  nurseries  to  keep  young 
trees  free  from  scale  and  aphids. 

14.  Carbolic  acid  emulsion  is  used  for  various  purposes.  It  is 
valuable  to  kill  aphids  and  soft-bodied  scale-insects  and  is  used 
also  for  insects  which  attack  the  roots  of  some  garden  crops.  It 
is  made  from  whale-oil  soap,  40  lbs.,  dissolved  in  40  gallons  of 
water  and  boiled  for  twenty  minutes  with  5  gallons  crude  carbolic 
acid.  This  product  is  diluted  at  the  rate  of  one  gallon  to  15  or 
20  gallons  of  water  for  use. 

3.  Repellants 

Repellants  include  any  substance  which  may  be  applied  to'  a 
plant  or  animal  to  prevent  insect  attack.  A  popular  notion  that 
any  vile-smelling  substance  will  repel  insect  attack  seems  to  have 
very  little  evidence  in  its  support.  Tobacco  dust,  air-slaked  lime, 
or  even  fine  road  dust,  thoroughly  covering  a  plant  will  prevent 
the  attack  of  various  flea-beetles  and  leaf-eating  beetles,  but  to  be 
successful  the  plants  must  be  frequently  dusted  and  kept  well  cov- 
ered. Bordeaux  mixture,  our  most  widely  used  fungicide,  when 
liberally  sprayed  on  potatoes  and  tomatoes,  acts  as  a  repellant  to 
the  little  black  flea-beetles  which  often  seriously  damage  the 
young  plants. 

The  various  fly-sprays  which  are  used  for  spraying  cattle  to 
prevent  the  annoyance  of  flies  act  merely  as  repellants. 

Fruit-trees  are  often  painted  with  a  thick  soap  solution  con- 
taining 1  pint  of  crude  carbolic  acid  to  10  gallons  as  a  repellant 
for  the  adult  borers  which  lay  their  eggs  on  the  bark. 

A  substance  which  has  come  into  prominence  in  the  fight 
against  the  gypsy  moth  in  New  England  is  tree  tanglefoot,  a  sticky 
substance  the  same  as  is  used  to  coat  fly-papers.  This  comes  in  the 
form  of  a  very  sticky  paste,  a  band  of  which  is  placed  around  the 
trunk  of  the  tree  and  which  prevents  the  ascent  of  caterpillars,  as 


INSECTICIDES  53 

it  will  remain  sticky  for  some  weeks.  It  may  be  used  in  the  same 
way  to  prevent  the  wingless  female  canker  worms  and  other 
wingless  insects  from  ascending  trees,  or  to  prevent  the  ascent  of 
caterpillars  on  unaffected  trees. 

Various  proprietary  insecticides  are  frequently  offered  for  sale 
with  wonderful  claims  for  their  effect  as  repellants,  but  only  in  rare 
cases  are  they  of  any  value  except  for  use  as  a  dust  as  already  sug- 
gested. One  of  the  most  common  fakes  of  this  sort  is  that  of  the 
itinerant  tree-doctor  who  offers  to  bore  a  hole  in  a  tree  and  plug 
it  with  sulfur  or  other  offensive  compounds,  which  will  effectively 
prevent  any  insect  or  fungous  depredations.  A  generous  price 
per  tree  is  charged,  which  is  the  only  "  effect  "  of  the  treatment. 

Bordeaux  mixture  is  not,  generally  speaking,  an  insecticide 
but  it  does  have  a  repelling  action  on  some  insects,  notably  the 
flea-beetles  which  attack  potatoes  and  tomatoes.  It  is  the  most 
widely  used  fungicide  and  it  or  lime  sulfur  "  summer  strength  " 
will  practically  always  be  included  in  the  spray  applied  for  insects, 
so  it  is  well  for  all  interested  in  spraying  to  be  familiar  with  bor- 
deaux. It  is  prepared  by  mixing  a  solution  containing  three  to 
five  pounds  copper  sulphate  (bluestone),  with  a  mixture  of  four 
to  six  pounds  lime.  These  may  be  in  from  5  to  25  gallons  of  water 
and  should  be  mixed  by  pouring  both  at  the  same  time  into  a 
third  container,  usually  the  spray  tank  or  barrel.  The  total 
liquid  from  the  above  amounts  should  be  50  gallons. 

Asphalt  paint  and  even  asphaltum  are  applied  to  trunks  and 
branches  of  trees  to  keep  out  borers.  Heating  is  generally  required 
and  the  application  is  somewhat  difficult  but  good  results  have 
been  obtained. 

4.  Gases 

Carbon  Bisuljid  (or  disulfid)  is  extensively  used  against  insects 
affecting  stored  goods  and  grains,  and  for  root-feeding  insects.  It 
is  a  clear,  volatile  liquid  giving  off  fumes  heavier  than  air.  It  may 
be  thrown  directly  onto  grain  without  injury  to  it  or  placed  in 
shallow  dishes.  For  grain  in  store  in  fairly  tight  rooms  apply  one 
pound  to  every  100  bushels,  distributing  the  bisulfid  over  the 
surface  or  in  pans  containing  not  over  one-half  to  1  pound  each. 
Make  the  enclosure  as  tight  as  possible,  covering  the  grain  with 
blankets  or  other  tight  cover,  if  necessary,  and  leave  for  twenty- 


54         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

four  hours.  Recent  experiments  have  shown  that  the  vapor  is 
much  less  effective  at  low  temperatures  and  that  the  dosage  must 
be  greatly  increased  at  temperatures  below  60°  F.  For  fumi- 
gating buildings  "  there  should  be  about  1  square  foot  of  evap- 
orating surface  to  every  25  square  feet  of  floor  area,  and  each 
square  foot  of  evaporating  surface  should  receive  from  one-half 
to  1  pound  of  liquid."  For  fumigating  clothing  or  household 
goods,  place  them  in  a  tight  trunk  and  place  an  ounce  of  liquid 
in  a  saucer  just  under  the  cover.  The  gas  is  exceedingly  explosive; 
allow  no  fire  or  light  of  any  kind  around  the  building  or  enclosure 
until  it  has  been  well  aired.  The  fumes  should  not  be  inhaled,  for 
though  not  seriously  poisonous,  they  have  a  suffocating  effect  and 
will  soon  produce  dizziness  and  a  consequent  headache.  The 
treatment  for  root-maggots  and  root-feeding  aphides  is  discussed 
in  connection  with  those  insects  (pages  317  and  435).* 

Hydrocyanic  Acid  Gas  is  extensively  used  for  the  fumigation 
of  nursery  trees  and  plants,  certain  greenhouse  insects,  pests  of 
dwelling  houses,  storehouses,  mills,  etc.  It  is  made  by  combining 
cyanide  of  potassium  or  sodium,  sulphuric  acid  and  water.  The 
gas  is  slightly  lighter  than  air  and  is  one  of  the  most  deadly  poisons 
known.  It  should  be  used  only  under  competent  direction  and 
by  persons  thoroughly  capable  of  understanding  the  directions 
and  carrying  them  out.  Under  such  circumstances  the  danger  is 
negligible.  Brief  directions  follow  but  these  should  be  supple- 
mented by  first-hand  advice  which  considers  the  local  factors. 

Take  for  each  100  cubic  feet  of  space  one  ounce  of  the  cyanide, 
one  ounce  of  the  acid  and  three  ounces  of  water.  JProvide  stone 
jars  which  will  not  be  filled  more  than  one-third  full  by  the  quantity 
of  materials  to  be  used.  Use  one  or  more  for  each  room,  accord- 
ing to  the  size  of  the  room.  Weigh  out  the  cyanide  and  place 
the  amount  for  each  jar  in  a  paper  bag  beside  the  jar.  Pour  the 
water  into  the  jar  and  then  add  the  acid,  stirring  gently  at  the 
time.  Arrange  the  material  in  this  manner  for  all  the  rooms. 
The  building  should  previously  have  been  made  as  nearly  air- 
tight as  possible.  An  exit  on  the  ground  floor  should  have  been 
provided  and  arranged  so  that  it  can  be  quickly  closed  and  pro- 

*  For  a  complete  discussion  of  the  use  of  this  gas,  see  Farmers'  Bulletin, 
145,  U.  S.  Dept.  Agri.,  and  see  page  184  below. 

Carbon  tetrachloride  is  now  used  for  some  purposes  in  much  the  same 
manner  as  carbon  bisulphide,  and  is  not  so  explosive. 


INSECTICIDES  55 

vision  for  opening  some  doors  or  windows  on  each  floor  from  the 
outside  should  have  been  made. 

Needless  to  say,  the  building  can  not  be  entered  during  the 
fumigation.  When  all  is  in  readiness  the  operator  or  operators 
should  start  on  the  upper  floor,  in  the  rooms  farthest  removed 
from  the  stairway  and  drop  the  bags  of  cyanide  quickly  into  the 
jars  of  liquid,  go  quickly  to  the  next  floor  below  and  repeat  the 
operation  and  so  on  to  the  ground  floor  and  from  there  outside, 
closing  and  locking  the  last  door.  The  building  should  be  locked 
and  placarded  and  it  is  well  to  have  a  watchman  to  warn  people 
from  the  vicinity.  After  12  to  24  hours  the  windows  and  doors 
should  be  opened  from  the  outside  and  the  building  allowed  to 
air  for  one  to  three  hours  when  it  will  be  safe  to  enter.  Inside 
doors  should  be  left  open.  A  thick  newspaper  should  be  placed 
under  each  jar  to  protect  the  floor  from  splashing  of  the  liquid 
which  may  occur  during  the  generation  of  the  gas,  which  may  be 
violent.  The  cyanide  used  must  be  98  to  99  per  cent  pure  and  the 
acid  of  specific  gravity  1.83,  commercial.  This  treatment  will 
kill  all  stages  of  insects,  also  rats  and  mice  but  will  not  injure  the 
contents  of  the  house  in  any  way  excepting  that  moist  foods 
should  not  be  exposed  to  the  gas.  Let  us  repeat,  however,  that 
the  gas  is  one  of  the  most  violent  poisons  known. 

Cyanide  fumigation  is  extensively  used  on  the  Pacific  Coast 
for  the  control  of  insects  on  fruit  trees,  these  being  fumigated 
under  specially  constructed  tents.  Dosage  tables  and  other  in- 
formation concerning  this  practice  should  be  secured  through  the 
California  Experiment  Station  at  Berkeley  where  Dr.  C.  W. 
Woodworth  has  largely  perfected  the  methods  used. 

Sulfur  Dioxid. — The  fumes  of  burning  sulfur,  mostly  sulfur 
dioxid,  have  long  been  recognized  as  a  standard  remedy  for  the 
fumigation  of  dwellings  and  barracks  for  insect  pests.  Successful 
fumigation  for  the  bedbug  has  been  reported  when  stick  sulfur  has 
been  burned  at  the  rate  of  2  pounds  per  1000  cubic  feet  of  space. 
The  chief  objection  is  the  strong  bleaching  effect  of  the  fumes  in 
presence  of  moisture  and  their  destructive  action  on  vegetation. 
Recently  this  gas  has  been  extensively  used  under  the  name  of 
"  Clayton  gas,"  for  the  fumigation  of  ships  and  ships'  cargoes,  par- 
ticularly grain.  It  is  forced  into  the  tight  hold  of  a  ship  by  special 
apparatus   and   is   exceedingly   penetrating   and   effective.     The 


56  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

germinating  power  of  seeds  is  quickly  destroyed,  but  they  are  not 
injured  for  food.  1  to  5  per  cent  of  the  gas,  with  an  exposure  of 
twenty-four  hours,  is  effective  for  most  seed  and  grain  pests.  It 
cannot  be  used  on  vegetation  or  for  moist  fruits. 

Tobacco  Fumes. — 'Tobacco  is  extensively  used  as  a  fumigant 
for  aphids  in  greenhouses  and  for  certain  plants,  such  as  melons, 
by  using  it  under  covers.  Several  forms  are  now  commonly 
used.  Tobacco  or  nicotine  extracts  are  sold  under  various  trade 
names,  and  are  volatilized  by  heating  either  with  a  small  lamp 
or  by  dropping  hot  irons  into  the  dishes  containing  the  fluid. 
The  same  material  may  be  purchased  in  the  form  of  paper  which 
has  been  saturated  with  the  extract  and  which  is  burned  accord- 
ing to  directions,  a  certain  amount  being  sufficient  for  so  many 
cubic  feet  of  space,  which  forms  a  more  convenient  method  of 
application.  Certain  finely  ground  tobacco  powders,  called 
"  fumigating-kind  "  tobacco  powder,  are  used  in  the  same  way 
and  are  much  the  cheapest  form  of  tobacco  for  fumigation, 
though  requiring  slightly  more  work  in  preparing  for  fumigation. 
These  tobacco  preparations  are  excellent  for  the  fumigation  of 
household  plants,  which  may  be  placed  in  a  closet  and  then 
fumigated  according  to  the  directions  of  the  particular  brand 
employed.  Melon  vines,  young  apple  trees,  bush  fruits,  and 
similar  outdoor  crops  may  be  effectively  rid  of  plant-lice  by 
fumigating  with  tobacco-paper  under  a  frame  covered  with 
canvas  or  muslin  sized  with  glue  or  linseed  oil.* 

5.  Application  of  Insecticides 

Insecticides,  especially  stomach  poisons  and  contact  poisons, 
are  usually  applied  in  the  form  of  a  spray  delivered  under  pressure 
by  a  force  pump,  the  liquid  being  broken  up  into  a  fine  mist  by 
some  kind  of  nozzle  constructed  for  that  purpose.  As  sprays 
they  are,  of  course,  always  mixed  with  water  according  to  pro- 
portions which  will  be  mentioned  at  the  proper  places.  In  place 
of  pure  water,  bordeaux  mixture  or  dilute  lime-sulphur  is  some- 
times used  and  the  spray  then  serves  the  double  purpose  of  con- 
trolling insects  and  plant  diseases.     In  some  cases  the  fungicide, 

*  For  further  discussion  of  Insecticides  see  Farmers'  Bulletin  127,  U.  S. 
Department  of  Agriculture. 


INSECTICIDES  57 

a  stomach  poison  and  a  contact  poison  are  all  mixed  together 
forming  what  might  be  called  a  "  complete  spray." 

Arsenical  poisons,  and  in  a  very  few  instances  contact  insec- 
ticides, are  sometimes  applied  in  the  dry  form  as  dusts,  the  process 
being  called  dusting  or,  less  properly,  dust-spraying.  Truck 
crops  may  be  dusted  on  a  small  scale  without  special  machinery 
and  the  method  is  therefore  often  more  convenient  for  the  small 
gardener  than  spraying.  Recent  experiments  have  shown  that 
dusts  are  as  effective  as  sprays  in  controlling  the  insects  which 
affect  most  orchard  fruits  and  foliage.  The  method  has  not  been 
generally  adopted  as  yet  for  the  reason  that  it  is  still  doubtful 
whether  dusts  as  at  present  used  will  entirely  control  the  fungous 
diseases  of  the  orchard.  This  in  spite  of  the  fact  that  dusting  was 
first  extensively  used  to  control  a  fungus  disease,  the  mildew  of 
grapes.  Dusting  has  many  advantages  over  spraying,  notably, 
its  greater  rapidity,  it  being  possible  for  one  outfit  to  dust  as  much 
in  a  day  as  several  spray  outfits  can  cover,  and  the  elimination  of 
the  necessity  to  provide  a  water  supply  for  the  sprayers,  also  the 
consequent  lightening  of  the  outfits  due  to  the  elimination  of  the 
water.  It  is  therefore  to  be  hoped  that  the  method  will  be  devel- 
oped so  that  it  is  applicable  for  all  the  pests  of  the  orchard. 

Stomach  poisons  are  frequently  used  in  the  form  of  baits 
rather  than  applied  directly  to  the  plants  to  be  protected.  In 
such  cases  substances  attractive  to  the  insects  are  poisoned  and 
placed  where  they  can  get  them  easily,  usually  near  the  plants. 
The  most  commonly  used  bait  is  poisoned  bran-mash  prepared 
according  to  a  formula  based  on  old  usage  but  perfected  at  the 
Kansas  Experiment  Station.     It  is  made  as  follows: 

Bran 20  lbs. 

Paris  green 1  lb. 

Cheap  sjTup 2  qts. 

Water 3^  gals. 

• 
Place  the  Paris  green  and  the  bran  in  a  tub  and  mix  thoroughly 

while  dry.  Dissolve  the  syrup  in  the  water  and  mix  this  with 
the  poisoned  bran,  stirring  thoroughly.  To  make  the  mixture 
more  attractive  to  many  insects,  especially  grasshoppers,  it  is 
flavored  with  oranges  or  lemons.  This  requires  three  oranges  or 
lemons.  They  are  chopped  into  fine  bits  and  the  chopped  fruits, 
juice  and  all,  are  added  to  the  mash  above  and  stirred  in  thoroughly. 


58         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

This  may  be  applied  broadcast,  preferably  late  in  the  evening  or 
very  early  in  the  morning  or  it  may  be  placed  in  small  quantities 
near  the  plants  liable  to  attack.  Chickens  should  be  kept  away 
from  the  mash. 

Poisoned  syrups  are  at  times  sprayed  on  plants  so  that  the 
adult  insects,  generally  forms  with  sucking  mouth  parts,  may  be 
killed  before  they  lay  their  eggs.  This  method  has  been  used  to 
some  extent  to  control  onion  maggots  by  killing  the  flies  which 
produce  them. 

6.  Stickers  or  Adhesives 

It  is  sometimes  necessary  to  use  some  material  with  the  in- 
secticide in  order  to  make  the  spray  stick  to  the  leaves  of  plants 
like  cabbage.  For  this  purpose  a  cheap  form  of  syrup  or  molasses 
is  sometimes  used.  This  is  used  also,  at  times,  to  make  the  spray 
attractive  to  the  insects  so  that  they  will  eat  larger  quantities  of 
it  and  be  more  quickly  killed.  Syrup  is  not  generally  as  good  a 
spreader  or  adhesive  as  some  other  materials.  A  soap  containing 
resin  is  as  effective  as  any  material  in  use.  This  material  may  be 
made  at  home  but  the  process  is  tedious  and  somewhat  messy 
and  it  will  be  more  simple  in  most  cases  to  purchase  it.  A  simple 
preparation  of  resin,  used  for  the  most  part  with  bordeaux  mixture, 
is  made  by  boiling  2  pounds  resin,  one  pound  sal  soda  and  1  gallon 
of  water  together  in  an  iron  kettle  for  one  to  two  hours.  This 
amount  is  needed  for  each  fifty  gallons  of  spray. 

Cactus  solution,  compounds  of  cstsein  from  milk  and  many 
other  substances  have  been  used  as  adhesives  and  spreaders  but 
their  use  is  not  yet  firmly  established  as  successful. 


CHAPTER  VI 
SPRAYING  AND  DUSTING  APPARATUS 

Atomizers. — Hand  atomizers  of  the  general  style  shown  in 
Fig.  26  may  be  purchased  at  any  hardware  store,  and  are  useful 
for  applying  soap  or  oil  solutions  to  a  few  house  or  garden  plants. 
They  are  not  adapted  for  more  extensive  use  and  to  try  to  spray 
many  plants,  or  a  tree,  with  them,  is  a  waste  of  time. 

Bucket  Pumys. — The  simplest  type  of  spray  pmnp  is  that 
made  to  use  in  a  bucket.     The  better  types  usually  cost  $5  to 


Fig.  26. — An  atomizer  handy  for  spraying  a  few  plants. 

$15,  the  cheaper  styles,  selling  for  $2  or  S3,  being  inferior  and 
unsatisfactory. 

There  is  as  much  difference  in  the  structure  of  bucket  pumps 
as  in  those  of  the  barrel  type,  and  many  of  the  statements  made 
below  concerning  the  latter  will  apply  also  to  bucket  pumps. 
The  bucket  pump  should  have  an  air  chamber,  so  that  a  steady 
pressure  may  be  maintained.  Some  firms  are  making  bucket 
pumps,  of  the  same  general  type  as  the  barrel  pump  shown  in  Fig. 
34,  which  are  very  satisfactory  in  this  regard.  A  foot-rest  attached 
to  the  pump  and  a  clamp  to  attach  the  pump  to  the  bucket  are 
useful  accessories. 

Many  firms  are  now  selling  these  pumps  mounted  in  large 
galvanized-iron  covered  buckets,  and  furnished  with  a  mechanical 
agitator.     This  is  a  desirable  arrangement,  for  the  buckets  are 

59 


60       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

much  larger  than  those  ordinarily  used,  thus  saving  frequent 
filling,  while  the  cover  prevents  slopping,  and  the  pump  is  always 
ready  for  use  without  the  necessity  of  hunting  up  a  bucket  and 


Fig.  27. — a,  a  cheap  type  of  bucket  pump  with  no  air-chamber,  which  will 
not  maintain  satisfactory  pressure;  b,  a  better  type  of  busket  pump 
with  small  air-chamber.     (Courtesy  Deming  Co.) 

then  cleaning  it,  which  is  necessary  after  using  a  bucket  which 
is  used  for  other  purposes. 

Bucket  pumps  are  useful  for  small  gardens  or  for  a  few  small 
trees  or  bushes. 

Knapsack  Pumps. — The  knapsack  pump  consists  of  a  copper 
or  galvanized-iron  tank,  carried  on  the  back  like  a  knapsack,  in 
which  is  mounted  a  bucket  pump  with  a  lever  handle  for  pumping. 
In  the  better  makes  this  handle  is  detachable  and  a  plain  handle 
may  be  attached  so  that  the  tank  may  be  used  as  a  simple  bucket 
pump,  for  which  a  foot-rest  is  attached  to  the  tank.  The  pump 
should  have  a  good  mechanical  agitator.  The  copper  tanks 
are  preferable,  for  bordeaux  mixture  will  soon  eat  through  gal- 
vanized iron.  Knapsack  pumps  are  useful  for  spraying  such 
crops  as  tomatoes,  melons,  etc.,  which  cover  the  ground  so  that 
it  is  difficult  to  drive  through  them  without  injuring  the  vines, 
crops  growing  on  steep  hillsides,  or  for  a  small  acreage  of  any 
garden  crops,  small  fruits,    or  small  trees.    The  main  objections 


SPRAYING  AND  DUSTING  APPARATUS 


61 


to  them  are  that  they  are  heavy  to  carry,  thus  Hmiting  their  use 
to  a  small  area;  they  frequently  slop  over,  and  wet  the  carrier's 
back  and  the  pumps  do  not  develop  sufficient  pressure  for  some 
kinds  of  work.  Consequently  they  are  not  as  much  used  as 
formerly,  but  are  useful  for  the  pur- 
poses indicated,  and  inasmuch  as 
they  may  also  be  used  as  a  simple 
bucket  pump,  they  are  to  be  pre- 
ferred to  them.  The  cost  varies 
from  $8  to  $12  or  $15. 

Compressed-air  Sprayers. — In  re- 
cent years  the  compressed  air  sprayer 
has  come  into  favor  for  use  in  small 
gardens.     It  consists  of  a  brass  tank 


Fig.  28. — Bucket  pump  mounted  in 
bucket,  and  mounted  in  tank  with 
agitator.     (Courtesy  Deming  Co.) 


Fig.    29. — Bucket    pump    with 
large  air-chamber,  which  will 
maintain  a  good  pressure. 
(Courtesy  F.  E.  Myers&  Bro.) 


which  is  filled  with  the  liquid;  the  air  is  compressed  by  an 
air-pump,  and  spraying  continues  until  the  pressure  runs  down, 
when  a  stopcock  is  turned  and  the  pressure  is  again  raised  by 
pumping.  The  tank  holds  from  3  to  5  gallons,  and  is  carried 
beneath  one  arm,  slung  by  a  strap  over  the  other  shoulder.  The 
chief  objections  to  this  type  are  that  it  is  not  very  convenient 
to  fill,  though   the   newer   models   are   much   improved,    is   not 


62       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


readily  repaired,  has  no  agitator,  and  requires  frequent  pumping. 

On    the  other  hand,  they  are   easily   carried,   do  not    leak,  and 

leave    both    hands  free,  so  that 

one  might  be  used  for  spraying 

a  small  tree  from  a  step-ladder. 

These     compressed-air     sprayers 

cost  from  $8  to  $20. 

Barrel  Pumps. — The  most  ser- 
viceable   spray    pump    for    the 

average  farm  is  the  barrel  pump. 

With  a  good  barrel  pump  100  to 

150  full-grown  apple  trees  may  be 

sprayed  in  a  day,  so  that  it  will 

be  found  sufficient  for  an  orchard 

of  500  trees  or  less.     By  using  a 

row-spraying   attachment,  a  few 

acres  of  potatoes  or  other   row 

crops    may  be  sprayed   with    a 

barrel  pump  miich  more  quickly 

than  by  hand.     In  buying  a  row 

attachment,  be  sure  that  it  is  ad- 
justable   for    rows    of    different 

widths.     A  good  barrel  pump  costs  from    $25  to  $50.     Most  of 

the  pmnps  sold  for    less    are  too  light  to  do  effective  work  or 

are  not  well  con- 
structed. Numerous 
pump  companies  ad- 
vertise in  the  agricul- 
tural papers  and  after 
considering  the  follow- 
ing points  one  may 
select  a  suitable  pump 
from  their  catalogs: 

1.  The  pump  should 
be  guaranteed  to  fur- 
nish two  nozzles  at  80 
to  lOOpounds'pressure 

Fig.  31.-The  knapsack  sprayer  in  use.  ^'^^  ordinary    pump- 

(Spramotor  Co.)  ing. 


Fig.  30. — One  of  the  best  types  of 
knapsack  sprayers.  Note  foot- 
rest,  agitator,  handle,  and  wide 
straps.     (Deming  Co.) 


Fia.  32. — Compressed-air  sprayer 
with  section  of  tank  removed 
to  show  air  pump  within. 


Compressed-air  sprayer  in  posi- 
tion to  use. 


Fig.  33. — An  undesirable  type  of 
barrel  sprayer  —  now  off  the 
market;  •  the  air-chamber  and 
other  parts  above  the  barrel 
render  it  top-heavy,  and  may 
be  easily  broken. 


Fig.  34. — A  desirable  type  of  barrel 
pump  embodying  most  of  the 
features  described.  (Morrill  & 
Morley.) 


63 


64   INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


2.  It  should  have  a  large  air  chamber  within  the  barrel,  and 
not  projecting  above  it 

3.  As  few  of  the  working  parts  of  the  pump  as  possible  should 
be  above  the  head  of  the  barrel,  as  exposed  parts  are  easily  broken. 

4.  The  cylinder,  plunger,  valves  and  working  parts  should  be  of 
brass.  The  handles  and  other  parts  commonly  made  of  cast  iron 
are  much  more  durable  when  made  of  malleable  or  galvanized  iron. 

5.  There  should  be  a  good  mechanical  agitator  of  the  paddle 
type,   preferably  arranged  so  that  it  can  be  worked  with  the 


Fig.  35. 


-Two  types  of  double-acting  lever  pumps,  to  be  mounted 
on  truck  and  connected  with  tank. 


pump  handle  without  operating  the  pump.  An  agitator  is 
essential  to  keeping  the  mixture  in  suspension.  Agitators  of  the 
so-called  "jet-type,"  in  which  a  stream  from  the  bottom  of  the 
cylinder  is  supposed  to  agitate  the  liquid,  are  unsatisfactory 
and  allow  a  loss  of  pressure  without  sufficiently  agitating  the 
liquid. 

6.  The  pump  should  be  so  attached  to  the  barrel  that  it  can 
be  quickly  removed  for  repairs.  Those  pumps  which  have  lugs 
for  attaching  the  pump  plate  to  the  barrel  are  much  better  than 
those  with  screws. 


SPRAYING  AND  DUSTING  APPARATUS 


65 


Fig.  36. — A  two-cylinder  pump  for  use  with  tank.     Good  capacity  and  easy 
operation  feature  this  type.     (Courtesy  the  Friend  Mfg.  Co  ,  Gasoort 

N.  Y.) 

r  >jirf'"  X-^  *"-'"*^™!  7.  The  valves,   with  their 

seats  or  cages,  should  be  readily 
removable  for  cleaning,  and 
should  be  so  constructed  that 
they  remain  evenly  ground. 

All  of  these  points  may  not 
be  embodied  in  anyone  pump, 
but  most  of  the  better  pump 
manufacturers  are  embodying 
these  features  in  their  newer 
models,  a  good  example  of 
which  is  shown  in  Fig.  34. 

Barrel,  knapsack,  and  bucket 
pumps  are  manufactured  which 
have  separate  tanks  for  oil  and 
water  which  are  mixed  in  a 
desired  proportion  and  sprayed 
Fig.  37. — Gasoline  power  sprayer,  com-  as     a     mechanical     mixture. 

plete     Note  widetread  steel  wheels,   Thev  have  been   found    unre- 

steel  tower  on  tank,  and  mtake  hose    ,.,,'. 

for  filling  tank  where  running  water    hable  m  COntrolhng  the  amount 

is  not  available;   3^^   h.p.,    4-cycle  of    oil,    and    are    not  now  in 

gasolme    engme,    will    mamtam    10 

nozzles  at  200  lbs.  pressure.  general  use 


66  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Horizontal  Pumps. — For  larger  orchards  and  shade  trees,  the 
double-acting  horizontal  pumps  which  are  operated  with  a  lever, 


Fig.  38. — One  of  the  latest  three-cylinder  power  pumps  designed  for  spray- 
ing shade-trees  and  woodlands. 


Fig.  39.-  -  Row-spraying  attachment  for  use  with  barrel  pump,  adjustable  for 
various  width  of  rows.     (Deming  Co.) 

as  shown  in  Figs.  35  and  36,  furnish  more  power  and  consequently 
make  more  rapid  work  possible.     They  are  mounted  on    100  or 


SPRAYING  AND  DUSTING  APPARATUS  67 

150-gallon  tanks  and  may  be  arranged  for  filling  the  tank  where 
running  water  is  not  availal)le.  These  pumps  cost  from  $30  to 
$50  and  will  maintain  100  to  125  pounds  pressure  with  four  to 
eight  nozzles.  They  are  usually  used  with  two  men  spraying 
and  another  driving  and  pumping,  or  a  fourth  man  pumps  and 
changes  places  now  and  then  with  the  driver,  as  the  operation 
of  this  type  is  rather  too  heavy  for  one  man  constantly. 

Power  Outfits. — For  orchards  of  much  over  500  trees  or  for 
extensive  shade  tree  work  a  gasoline  power  outfit  is  more  econom- 
ical and  enables  a  large  area  to  be  covered  more  quickly,  which  is 
often  a  most  important  consideration.  Most  of  the  pump  manu- 
facturers and  many  gas  engine  companies  are  selling  such  outfits 
mounted  upon  a  truck,  with  spray  tank,  and  tower  complete  for 
from  $250  to  $1000. 

Traction  Sprayers. — For  a  small  acreage  of  potatoes  or  other 
row  crops,  a  barrel  pump  with  row  attachment  is  very  satisfac- 
tory, but  for  any  considerable  acreage,  a  two-wheeled  traction 
sprayer  is  much  more  economical  of  labor  and  time  which  are 
the  two  chief  items  in  the  cost  of  spraying.  Such  traction 
sprayers  are  made  of  widely  different  types,  the  power  in  all 
cases  being  furnished  by  a  gear  or  chain  which  operates  the  pump 
from  the  wheels.  The  mechanical  construction  of  the  traction 
sprayers  should  be  carefull}''  studied,  and  if  possible  tested,  before 
purchasing,  as  they  differ  greatly  in  efficiency.  The  better  types 
cost  from  $100  to  $200  and  usually  have  attachments  adapting 
them  for  all  sorts  of  row  crops,  such  as  potatoes,  strawberries, 
bush  fruits,  grapes,  etc.,  which  require  different  styles  of  piping 
to  direct  the  nozzles  properly. 

Several  traction  sprayers  are  sold  for  orchard  work  but,  though 
they  are  fairly  satisfactory  for  small  trees,  they  do  not  develop 
enough  power  for  spraying  large  trees,  and  have  a  heavy  draft. 

Various  other  types  of  spraying  machines  have  been  tested 
and  some  of  them  put  on  the  market.  Among  these  may  be 
mentioned  gas-sprayers,  where  the  gas  in  cylinders  under  pres- 
sure is  used  to  furnish  the  pressure;  and  compressed  air  sprayers, 
where  air  compressed  at  a  central  station  in  large  cylinders  takes 
the  place  of  gas.  These  have  some  great  advantages  but  diffi- 
culties which  arise  in  practical  operations  have  kept  them  from 
being  widely  used. 


68 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Nozzles. — A  good  nozzle  is  as  essential  as  a  good  pump  for  suc- 
cessful spraying.  The  best  nozzles  now  in  common  use  are  of 
three  types. 

The  Vermorel  type  consists  of  a  small  chamber  into  which  the 
liquid  is  admitted  at  a  tangent  and  leaves  through  a  small  hole  in  a 
removable  cap,  thus  making  a  fine,  cone-shaped  spray.     A  small 


Fig.  40. — A  good  type  of  geared  sprayer  for  row  crops. 

pin,  with  a  spring  to  hold  it  back  when  not  in  use,  serves  as  a  dis- 
gorger  to  remove  any  sediment  which  may  clog  the  outlet.  This 
type  of  nozzle  is  made  in  many  slightly  different  styles  and  often 
sold  under  trade  names,  such  as  the  Demorel,  Mistry  and  others. 
A  slightly  modifi(-d  form  has  no  spring  attached  to  the  disgorger, 
but  has  a  loose  cap  which  is  held  away  from  the  pin  by  the  force  of 
the  liquid,  and  the  outlet  is  disgorged  by  simply  pressing  the  cap 
down  on  the  pin.  Such  are  the  Spramotor  (Spramotor  Mfg.  Co.) 
and  Vapor-Mist  Nozzles  (Field  Force  Pump  Co.)  and  are  disgorged 
rather  more  easily  than  those  with  springs. 

Disc  type. — An  evolution  from  the  older  type  of  nozzles  now 
in  almost  universal  use  is  the  disc  nozzle.     This  has  a  broader  and 


SPRAYING  AND  DUSTING  APPARATUS 


69 


flatter  chamber  and  is  variously  adapted  to  give  to  the  liquid  a 
strong  rotary  motion  which  helps  to  break  up  the  liquid  into  a 


Fig.  41. — Row  sprayer  applying  arsenate  of  lead  to  potatoes,  showing 
arrangement  of  nozzles  to  cover  vines.     (After  Britton.) 

fine  spray.  There  are  usually  interchangeable  discs  with  aper- 
tures of  varying  sizes  adapted  for  all  degrees  of  fineness  of  spray 
and   for  varying  the  quantity  of  liquid  delivered.     Under  ordi- 


FiG.  42  — Vermorel,  bordeaux,  and  disk  type  of  nozzles. 

nary  conditions  only  one  of  these  is  needed  on  a  rod  to  deliver  all 
the  liquid  that  the  operator  can  handle  properly.  This  does 
away  with  the  necessity  for  "  Y's  "  and  lightens  the  rod.  The 
illustration  (Fig.  44)  shows  many  of  the  modern  types. 


70 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Bordeaux    nozzle  is  of    entirely  different    structure,    the 
spray    being  formed  by  a  straight  stream    hitting    a    Up  which 

breaks  it  into  a  fan-shaped  spray,  the 
fineness  of  the  spray  being  governed  by 
the  width  of  the  aperture.  To  unclog 
the  nozzle  the  core  through  which  the 
stream  emerges  is  reversed,  thus  giving 
a  straight  stream  and  clearing  the  nozzle 
immediately.  For  this  reason  the  bor- 
deaux nozzle  is  particularly  adapted  to 

traction  sprayers  where  several  nozzles 
Fig.  43. — Ande  form  of  disk  j        j    -x   •  -  i 

type    nozzle,    particularly  are  used  and  it  IS  necessary  to  unclog 

useful  for  orchard  spraying,  them   quickly.     It  is  usually  preferred 


(Friend  Mfg.  Co.) 


for  garden  and  row   crops,   and   some 


prefer  it  for  tree  work,  though  it  is  not  as  widely  used  for  that 
purpose  as  the  previous  types. 

The  bordeaux  nozzle    is  of    great   value  for  applying   white- 
wash, a  purpose  for    which    the  spray    outfit    may  well  be  used 


A  #  #  # 


Fig.  44. — Disk  Nozzles.  Top  row  Oeft 
to  right):  Atomic,  New  Eclipse, 
Whirlpool,  Excelall.  Middle  row: 
Tiger  Strainer,  Fog,  Bean  Mist, 
Nonclog  Atomic.  Lower  row  ."Friend 
Regular,  Friend  Angle,  Scientific, 
Mistry  Jr.  (From  H.  L.  Crane,  W. 
Va.  Agr.  Expt.  Sta.) 


4  4 


Fig.  45. — Types  of  bor- 
deaux nozzles.  (From 
H.  L.  Crane,  W.  Va. 
Agr.  Expt.  Station.) 


during  the  off  season.     It,  with  the  disk  type,  will  be  found  to  fill 
most  of   the  needs  of  today  for  nozzles. 

Rolid  stream  nozzles.— For  special  purposes,  such  as  spraying 
woodlands  or  spraying   large  trees  in  parks  or  on  citj'  streets  or 


SPRAYING  AND  DUSTING  APPARATUS 


71 


Fig.  46. — Spray-guns  in  operation 

even  for  spra3ang  old  and 
very  tall  apple  trees,  a  type 
of  nozzle  which  delivers  a 
solid  stream  of  small  di- 
ameter through  a  nozzle  end- 
ing in  a  tube  of  about  one- 
eighth  inch  diameter  for  two 
to  five  or  six  inches,  is  used. 
This  requires  a  high  pressure 
and  forces  the  liquid  high  in 
the  air  where  the  pressm-e 
against  the  air  tends  to  break 
it  up  into  a  mist.  For  or- 
dinary work  in  the  orchard 
this  type  is  not  available. 

Spray-guns. — A  recent  de- 
velopment of  the  spray  nozzle 
of  the  ordinary  type  and  the 
solid  stream  nozzle  is  the 
spray  gun.  This  is  a  nozzle 
which  can  be  made  to  deliver 
a  mist  lil<;e  the  ordinary  yiq.  47 
nozzle  or  a  solid  stream  or 


(Friend  Mfg.  Co.) 


Solid  stream  nozzle  in  operation. 
(Courtesy  the  Bean  Spray  Pump  Co.) 


72  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

almost    any   gradation    between    the  two.     It    delivers   a    large 
amount  of  liquid  and  will  greatly  reduce  the  time' required  to 
spray  an  orchard,  especially  where  the 
trees  are  large.     Like  the  solid  stream 
nozzle  it  requires  a  high  pressure,    at 
least  250  to  300  pounds  being  desirable 


Fig.    48.-Spray-guns:    a.  ^^^^    49.-Bamboo    exten- 

Friendtype.  (Friend  Mfg.  ^^o"    ^°f    .^J  j^f*'     ^^^ 

Co.)  b.Bean  type.    (Bean  i^o"  ^^^  with  drip-guard 

,  Spray  Pump  Co.)  at  right. 

for  good  work.       Several  types  are  on  the  market  and  while  they 
are  new  to  the  industry  they  have  already  shown  that  effective 


SPRAYING  AND  DUSTING  APPARATUS 


73 


insect  and  disease  control  can  be  secured  with  them.  The  spray- 
gun  is  used  without  a  rod,  it  being  long  enough  to  be  handled 
without  the  rod. 

Extension  rods. — In  orchard  spraying  where  the  spray  gun  is 
not  used  an  extension  rod  is  a  necessity.  This 
may  be  a  bamboo  rod  with  a  brass  or  aluminum 
pipe  inside,  or  it  may  be  merely  an  iron  pipe, 
one-fourth  inch  size.  I^engths  used  vary  with  the 
size  of  the  trees,  ranging  from  eight  feet  to  twelve  fig.  50. — 45-de- 

feet.     It  is  well  to  insist  on  a  rod  of  sturdy  con-      gree  elbow  for 

attaching  noz- 


zles to  end  of 
rod  for  orch- 
ard  spraying. 


struction  when  purchasing  as  one  which  is  likely 
to  pull  apart  at  the  connections  and  leak  is  a 
nuisance. 

Where  the  angle  type  of  nozzle  is  not  used  it  is  a  good  plan  to 
connect  the  nozzle  with  a  45-degree  elbow  in  order  that  the  spray 

.      may  be  more  easily  directed 
toward  the  tree. 

For  low-growing  bushes 
and  truck  crops  a  short  rod 
with  the  nozzle  attached  at 
right  angles  will  be  found 
useful  as  it  will  enable  one 
to  spray  the  under  side  of 
these  plants. 

Spray  hose. — Use  only  the 
i)est  spray  hose  obtainable. 
The  one-half  inch  size  is  most 
commonly  used  for  orchard 
spraying.  This  should  be 
guaranteed  against  a  work- 
ing pressure  of  300  pounds. 
Where  a  spray  gun  is  used  it 
is  necessary  to  have  three- 
capacity.     Quarter  or  three- 


FiG.  51. — Spraying  squash  with  undsr- 
spray  nozzle  at  right  angle  to  rod. 


quarter  inch  hose   of  still  higher 

eighths  inch  sizes  are  used  for  bucket  pumps. 

A  common  mistake  is  using  hose  leads  which  are  too  short. 
Twenty-five  feet  should  be  the  minimum  and  fifty  feet  is  better. 
This  enables  the  operator  to  get  around  the  tree  and  to  keep  far 
enough  away  from  the  outfit  so  that  the  spray  will  not  blow  over 
the  driver,  sprayer  and  team. 


74  INSECT  PESTS  OF  FARM  GARDEN  AND  ORCHARD 

Connections  and  Cut-offs. — Hose  connections  are  important. 
Nothing  is  more  aggravating  than  to  have  the  hose  pull  loose 
from  its  connections  while  operations  are  in  progress.     To  prevent 


Fig.  52. — Spray  hose  connection,  long  shank  type  and  spray  hose  mender. 

(The  Bean  Co.) 

this,  use  only  connections  with  long  shanks  which  may  be  fastened 
with  two  hose-clamps  over  each  shank.  Fig.  52  shows  this  type 
of  connection  and  an  adaptation  of  it  used  for  mending  breaks  in 
hose  or  in  splicing  permanently  two  lengths  of  hose.  A  cut-off 
at  each  rod  is  necessary  and  this  should  be  of 
a  leak-proof  type.  A  three-way  cut-off  at  the 
pump  is  also  necessary  where  there  are  two  lines 
of  hose  operating  With  these  there  is  complete 
control  of  the  spray  and  one  line  can  stop  for 
repairs  while  the  other  continues  to  work. 

Towers. — Many  operators  like  to  use  a  tower 
for  spraying  large  trees  and  many  of  the  power 
sprayers  are  equipped  with  towers.  Their 
value  is  questionable,  however,  and  many 
laborers  refuse  to  work  in  them.  It  is  quite 
^shut-off  which°al-  probable  that  just  as  good  work  can  be  done, 
lows  the  hose  lead  in  most  cases,  by  using  longer  rods  and  reach- 

bendk^l  ^s  also  ^^^  ^^^  ^^P  ^^  ^^^  ^^^^  from  the  spot  nearest  it 
very  convenient,  at    the    base  of  the  trunk.     In  most  cases  the 
(,  rien         g.    o.;  Qpgj.g^^Qj.  ^j}j  ]-,g  j^g^  g^g  jjgg^p  ^]^g  ^q^  jj^  ^j^jg  posi- 
tion as  he  is  when  on  the  tower.     The  spray-gun  does  away  with 
the  need  for  the  tower  where  it  is  used  as  it  will  reach  the  top  of 
the  tallest  tree. 

Strainers. — To  obviate  the  delay  caused  by  nozzles  clogging 
with  dirt  and  sediment,  strain  all  mixtures  through  a  fine  copper 
strainer  when  filling  the  spray  tank.  Have  the  tank  tight  and 
see  that  it  is  clean  before  filling. 


SPRAYING  AND  DUSTING  APPARATUS 


76 


Dusting  Apparatus. — The  simplest  method  of  applying  dusts 
is  b}'  means  of  a  perforated  can  or  a  cheese-cloth  or  muslin  bag 
and  much  dust  is  still  applied  to  garden  crops  in  this  way  Dust 
bellows  to  force  dust  into  cracks  for  household  pests,  or  to  dis- 
tribute it  more  economically  and  evenly  on  plants,  represent 
the  next  step.  Various  small  dusters,  but  with  larger  capacity 
than  the  bellows,  are  used  for  small  plantings.  These  are  usually 
of  the  plunger  type  and  the  dust  is  puffed  out  rather  than  de- 
livered continuously.  Dusters  with  a  rotary  fan  or  blower,  de- 
livering the  dust  in  a  continuous  stream  are  made  in  many  sizes. 
Some  are  operated  by  hand, 
others  are  geared  to  the  truck 
upon  which  they  are  hauled 
so  they  operate  only  when 
the  truck  is  in  motion  and 
some,  the  more  modern  or- 
chard outfits,  are  supplied 
with  power  from  a  gasoline 
engine.  All  tj^pes  have  their 
uses  but  we  are  more  con- 
cerned with  the  commercial 
forms  than  with  the  more 
primitive  apparatus.  Or- 
chard dusters  operated  by 
hand  are  not  satisfactory  for  use  on  any  large  scale.  The  power 
dusters  on  the  market  are  quite  efficient  and  will  deliver  large 
quantities  of  dust  in  dense  clouds  which  have  considerable  carrying 
power.  Dusting  machines,  owing  to  their  more  hmited  use, 
have  not  been  mechanically  perfected  to  the  same  degree  as  the 
sprayers  but  they  undoubtedly  will  keep  pace  with  the  require- 
ments as  they  come  into  general  use. 

Dusting  mixtures  are  composed  of  arsenate  of  lead  or  of  cal- 
cium mixed  with  some  other  substance  which  acts  as  a  carrier. 
The  carrier  is  often  the  fungicide  or  is  a  mixture  of  the  fungicide 
with  some  inert  material  such  as  land-plaster  or  gypsum.  The 
common  formulas  call  for  from  10  to  15  pounds  arsenate  with  85 
to  90  pounds  finely  ground  sulfur,  a  special  grade  being  pro- 
duced for  this  purpose.  An  inert  material  may  displace  any 
part  of  the  sulfur  but  it  is  not  the  common    practice   to   dilute 


Fig.  54. — Spraying  with  power  outfit  from 
a  tower.     (Bean  Spray  Pump  Co.) 


76       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Fig.  55. — Orchard  duster  in  operation.     Courtesy  the  Niagara 
Sprayer  Co.,  Middleport,  N.  Y. 


SPRAYING  AND  DUSTING  APPARATUS 


77 


the  mixture.  Mixing  is  best  accomplished  by  machinery  con- 
structed for  the  purpose.  The  best  means  is  to  gi-ind  the  ingre- 
dients together.  Until  methods  of  mixing  ai'e  better  standardized 
it  will  be  wise  for  the  user  to  get  his  materials  ready-mixed. 


Fig.  56. — ^Another  make  of  duster.     (The  Dust  Sprayer  Mfg.  Co., 
Kansas  City,  Mo.) 

Dry  powdered  bordeaux  mixture  is  being  used  to  some  extent 
as  the  fungicide  in  dusting  formulas  but  is  still  in  the  experimental 
stage. 

Other  mechanical  devices  for  applying  poisons  and  controlling 
insects  will  be  discussed  in  connection  with  the  group  of  insects 
for  which  they  are  most  used.  * 

*  For  further  information  concerning  the  appHcation  of  insecticides  see 
the  following:  Farmers  Bulletin  908  (U.  S.  Dept.  Agr.)  "Information  for 
Fruit  Growers  About  Insecticides,  Spraying  Apparatus  and  Important 
Insect  Pests,"  A.  L.  Quaintance  and  E.  H.  Siegler. 


CHAPTER  VII 

Insects  Affecting  Grains,  Grasses,  Forage  and  Miscellaneous 

Crops 

Several  of  our  worst  insect  pests  live  normally  in  grass  land 
but  when  they  become  numerous  feed  upon  grains  and  various 
forage  and  garden  crops,  so  that  they  are  not  readily  classed  as 
enemies  of  any  one  crop,  and  will  therefore  be  discussed  together. 

White  Grubs  * 

Among  the  most  common  pests  of  corn,  strawberry  beds, 
and  garden  crops  are  the  large  white  grubs  which  feed  upon 
the  roots  and  often  kill  the  plants.  Their  habit  of  lying  curled 
up  in  a  semicircle,  and  the  large  brown  head,  white  body,  and 
enlarged  abdomen,  at  once  distinguish  them  from  other  forms 
of  grubs.  Although  they  are  very  similar  in  color  and  form, 
there  are  numerous  species,  all  of  which  are  the  young  of  different 
species  of  the  large  brown  May-beetles  or  June-bugs,  as  they  are 
commonly  called,  which  frequently  fly  into  lights  in  late  spring. 

Life  History. — The  eggs  are  laid  mostly  in  June,  preferably 
in  grass  land,  but  also  in  corn  fields  and  gardens.  The  egg  is 
of  a  broad  oval  shape,  pure  white,  about  one-tenth  inch  long, 
and  is  laid  in  a  small  ball  of  earth  a  half  inch  in  diameter,  from 
1  to  5  inches  below  the  surface.  The  eggs  hatch  in  about  two 
weeks,  most  of  them  hatching  by  the  middle  of  July.  The 
young  grubs  feed  upon  plant  roots,  and  grow  slowly,  as  it  re- 
quires two  years  or  more  for  them  to  become  full-grown.  In 
the  fall  they  burrow  down  in  the  soil,  gradually  going  deeper 
as  frost  approaches  until  by  the  first  freeze  most  of  them  are 
from  7  to  14  inches  deep.     The  next  year  they  do  much  more 

*  Lachnostema  spp.  Family — ScaraboeidcB.  See  S.  A.  Forbes,  Bulletin  116, 
Illinois  Agricultural  Experiment  Station,  and  J.  J.  Davis,  Farmers'  Bulletin 
940,  U.  S.  Dept.  of  Agr. 

78 


INSECTS  AFFECTING  GRAINS,  GRASSES,  ETC. 


79 


serious  damage,  and  land  which  has  been  in  sod  and  then 
planted  in  corn,  strawberries,  or  other  crops  of  which  they  are 
fond,  is  often  so  full  of  the  grubs  that  the  crops  are  ruined.  In 
1895  an  Illinois  field  of  250  acres  which  had  been  in  grass  for 
twenty  years  was  so  injured  that  the  sod  could  be  rolled  up 
like  a  carpet  over  the  entire  field.  It  is  not  surprising,  therefore, 
that  Professor  Forbes  records  finding  as  many  as  thirtA^-four  grubs 
to  the  hill  of  corn  in  another  Illinois  field  which  had  previously 
been  in  sod.     Where  sod  is  taken  into  greenhouses  the  grubs 


Fig.  57. — Lachnosterna  arcuata:  a,  beetle;  b,  pupa;  c,  egg;  d,  newly-hatched 
larva;  e,  mature  larva;  /,  anal  segment  of  same  from  below,  a,  b, 
e,  enlarged  one-fourth;  c,  d,  f,  more  enlarged.  (After  Chittenden, 
U.  S.  Dept.  Agr.) 

often  become  serious  pests.  When  the  grub  is  two,  or  possibly 
sometimes  three  years  old,  it  forms  a  small  oval  cell  from  3  to 
10  inches  below  the  surface  and  there  changes  to  a  soft,  white  pupa, 
sometime  in  June  or  July.  The  pupal  stage  lasts  slightly  more 
than  three  weeks,  and  in  August  or  September  the  adult  beetle 
wriggles  out  of  the  pupal  skin,  but  remams  in  the  pupal  cell 
until  the  following  spring,  when  it  comes  forth  fully  hardened. 
Thus  three  full  years  are  occupied  b}-  the  life-c3'-cle  of  each  brood, 
though  grubs  in  all  stages  of  development  may  be  found  in  the 
soil  every  year. 

The  adult  beetles  feed  at  night  upon  the  foliage  of  various 
trees.  They  hide  in  the  soil  during  the  da}^,  migrate  to  the  trees 
at  dusk,  and  return  to  the  fields  just  before  daybreak.  The 
different  species  have  favorite  food  plants,  but  all  of  our  common 
deciduous  shade  and  forest  trees  are  more  or  less  eaten,  poplar, 


80         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

willow,  and  maple  being  particularly  relished.  On  a  warm  evening 
the  beetles  may  often  be  heard  feeding  and  their  work  may  be 
identified  by  the  ragging  of  the  foliage,  as  if  it  had  been  torn. 

Control. — As  allowing  land  to  remain  in  grass  for  several  years 
is  conducive  to  the  increase  of  the  grubs,  a  frequent  rotation  will 
prevent  their  multiplication,  the  grass  being  followed  by  potatoes, 
buckwheat,  small  grains,  or  some  crop  not  seriously  injured  by 
them. 

As  the  beetles  remain  in  the  pupal  cells  over  winter  and  are 
tender  and  not  fully  hardened,  deep  plowing  and  thorough  har- 
rowing in  fall  or  early  spring  will  kill  large  numbers  of  them 
by  breaking  open  the  cells  and  exposing  them  to  the  weather 
and  by  burying  and  crushing  them. 

Swine  will  gorge  themselves  on  grubs  in  badly  infested  land, 
and  if  confined  so  that  they  will  thoroughly  root  it  over,  will 
very  effectually  rid  it  of  them.  Flocks  of  chickens  or  turkeys 
following  the  plow  will  catch  a  considerable  number  of  grubs, 
as  do  the  crows  and  blackbirds,  which  pay  for  the  corn  they  eat 
by  the  war  they  wage  on  grubs. 

The  beetles  may  be  jarred  from  the  trees  upon  which  they  are 
feeding  in  the  cooler  part  of  the  night  and  collected,  as  is  exten- 
sively done  in  Europe.  Lanterns  hung  over  pans  or  tubs  contain- 
ing water  with  a  surface  film  of  kerosene  placed  near  the  trees  on 
which  they  feed,  will  catch  large  numbers  on  warm  nights  when 
they  are  flying. 

Wireworms  * 

Wireworms  are  hard,  shining,  slender,  cylindrical,  brown 
larvae  about  three-quarters  to  1  inch  long,  which  bore  into  the 
seed  of  corn,  wheat  and  other  grains,  often  necessitating 
replanting,  and  also  feed  on  their  roots,  as  well  as  on  potatoes, 
turnips,  and  many  garden  crops.  They  are  the  young  stage  of 
brownish  beetles  of  the  family  Elateridce,  which  from  their 
habit  of  snapping  their  bodies  up  in  the  air  are  known  as  "  click 
beetles."  The  beetles  are  one-half  to  three-quarters  inch  long, 
decidedly  flattened,  dark  brown,  often  with  darker  markings,  with 
short  heads,  and  shield-shaped  thoraxes,  as  shown  in  Fig.  58. 
Although  the  common  wireworms  look  much  alike,  examination 

*  Family  Elateridce. 


INSECTS  AFFECTING  GRAINS,  GRASSES,  ETC. 


81 


usually  reveals  that  they  belong  to  several  species  which  are  dis- 
tinguished by  a  comparison  of  the  caudal  segments,  as  shown  in 
Fig.  59. 

Life     History.  —  The 
life  history  is  very  simi- 
lar to  that  of  the  white 
grubs,  except  that  from 
three  to  five  years  are 
required  for  the   com- 
plete life    cycle.      The 
eggs  are  deposited  in  old 
sod  land,  which  is  the 
favorite  breeding 
ground.      The  detailed  life    his- 
tories   have    not    been    carefully 
studied,  but  the  second  year  after 
grass  land   has  been   planted   in 
grain  is  that  in  which  the  worst 
injury   occurs,    particularly  with 
corn,  upon   which   the  attack  is 
more  concentrated  than  with  small 
grains.     The    larvae   become  full 
grown  in  midsummer,  form  small 
cells  in  the  soil  and  in  them  trans- 
form to   pupae.      Three   or  four 
weeks  later  the  adult  beetles  shed 
the  pupal  skins,  but  few  of  them 
make   their  way  to  the  surface 
during  the  fall,  most  of  them  re- 
maining in  the  pupal  cells  until 
the  following  spring. 

Control.— As  they  resemble  the 
white  grubs  in  life-cycle,  so  the 
means  of  control  are  similar.     By 

plowing  in  late  summer  or  early  Fig.  58.—^,  beetle  of  wheat  wire- 
p  n         ,  ,,  111  •        p  "         worm  (Agriotes  mancus)  X4:  B,  D, 

fall  and  thoroughly  harrowmg  for      beetle  (X4)  and  wireworm  (X7)  of 


c: 


a  month  or  so,  large  numbers  of 
the  pupae  and  newly  transformed 


Drasterius  elegans;  C,  the  corn  wire- 
worm  (Melanotus  cribulosus)  X4^. 
(After  Forbes.) 


82       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


beetles  will  be  destroyed.  When  the  wireworms  are  numerous  in 
restricted  areas,  as  they  often  are  on  spots  of  low  moist  land,  they 
may  be  effectually  trapped  with  but  little  labor  by  placing  under 
boards  bunches  of  clover  poisoned  with  Paris  green.  A  short  rotation 
of  crops  in  which  land  is  not  allowed  to  remain  in  grass  for  any 
length  of  time  will  prevent  their  increase.  Many  remedies  have 
been  suggested  for  these  pests  but  few  of  them  have  proved 
to  have  much  merit  in  careful  tests.  Coating  the  seed  with  gas 
tar,  as  is  done  to  protect  it  from  crows,  has  been  very  widely 
practiced,  and  though  previous  experiments  indicated  that  it  could 
not  be  relied  upon,  Dr.  H.  T.  Fernald  conducted  tests  in  Massa- 
chusetts in  1908  and  1909  in  which  seed  coated  with  gas-tar 
and  then  dusted  in  a  bucket  of  fine  dust  and  Paris  green  sufl&- 


FiG.  59. — Ay  last  segment  of  Melanotus  communis,  dorsal  view  (After  Forbes); 
B,  the  wheat  wireworm,  Agriotes  mancus — a,  b,  c,  d,  details  of  mouth- 
parts,  enlarged;  C,  caudal  segment  of  the  wireworm  of  Drasteterius 
elegans;  D,  caudal  segment  of  the  wireworm  of  Asaphes  decoloratus, 
much  enlarged.     (A,  C,  D,  after  Forbes;  B,  after  Slingerland.) 

cient  to  give  the  corn  a  greenish  color,  was  effectively  protected, 
the  treatment  seeming  to  act  as  a  repellant,  and  not  affecting 
the  germination  of  the  seed. 

The  Stalk-borer  * 

This  species  may  well  be  called  the  stalk-borer,  for  it  not  only 
tunnels  the  stalks  of  potatoes — being  often  called  the  potato  stalk - 
borer — and  tomatoes,  but  frequently  infests  corn,  cotton  and  a  long 
list  of  garden  crops,  grains,  grasses,  flowering  plants,  and  various 
common  weeds.  Apparently  the  latter,  such  as  ragweed,  cockle- 
bur  and  the  like,  are  its  normal  food  plants,  and  when  they  are 
destroyed  or  where  more  tender  cultivated  plants  are  near  by, 
it  attacks  whatever  is  available.  Two  or  three  nearly  related 
species  have  very  similar  habits. 

*  Papaipema  nitela  Gn.     Family  NoctuidoB. 


INSECTS  AFFECTING  GRAINS,  GRASSES,  ETC. 


83 


The  adult  moth  (Fig.  60)  is  a  fawn-gray  or  mouse  color,  with 
the  outer  third  of  the  fore-wings  paler  and  bordered  within  by  a 
whitish  cross-line. 

Life  Histonj. — The  eggs  are  laid  in  the  fall  on  the  stems  of 
weeds  and  grasses,  in  masses  of  fifty  or  sixty,  near  the  ground. 
They  are  about  one-fiftieth  inch  in  diameter,  circular,  grayish 
in    color,    with   radiating  ridges.     They   hatch   in   late   May   in 


■^ 


FiQ.  60. — The  stalk-borer  (Papaipema  nitella  Gn.):  a,  adult;  b,  half-grown 
larva;  c,  mature  larva  in  burrow;  d,  side  of  one  of  its  segments;  e, 
pupa— all  slightly  enlarged.     (From  Chittenden,  U.  S.  Dept.  Agr.) 

southern  Minnesota  and  the  young  caterpillars  at  once  commence 
to  mine  small  galleries  in  the  leaves  of  the  food  plants,  soon 
riddling  the  leaves.  In  a  few  days  they  work  down  to  the  bases 
of  the  leaves  and  enter  the  stalks,  which  they  tunnel  out  and  not 
infrequently  leave  one  plant  and  migrate  some  little  distance 
before  entering  another.  Infested  plants  are  readily  recognized 
by  the  wilting  of  the  parts  above  the  larva,  the  work  in  corn 
being  particularly  noticeable  and  having  given  the  local  name 
of  "  heart-worm."  The  larvae  become  full  grown  about  the 
first  of  August.  They  are  readily  recognized  by  the  peculiar 
markings  of  the  body  (Fig.  60,  6).  The  larva  is  about  an  inch 
long  and  varies  from  purplish  to  whitish  brown,  and  is  marked 


84         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

with  five  white  stripes,  one  along  the  middle  of  the  back,  and  two 
on  each  side.  These  side  stripes  are  absent  on  the  first  four 
segments  of  the  abdomen,  giving  the  larva  an  appearance  as  if 
it  had  been  pinched  or  injured  there.  As  the  larva  matures  the 
stripes  become  fainter.  When  ready  to  pupate  the  larva  cuts  a 
hole  through  the  side  of  the  stalk,  and  then  transforms  to  the 
brown  pupa  in  the  lower  part  of  the  stalk.  The  pupal  stage  lasts 
about  two  or  three  weeks,  and  the  moths  emerge  in  late  August, 
there  being  but  one  generation  a  year. 

Usually  the  injury  to  crops  is  onlj^  in  the  outer  rows,  to  which 
the  larvae  have  migrated  from  weeds  growing  along  the  edges, 
or  in  fields  which  have  been  weedy  in  early  spring,  or  where  the 
weeds  have  been  allowed  to  get  a  start  before  being  culti- 
vated out. 

Control. — From  the  life  history  and  habits  it  is  obvious  that 
clean  farming  is  the  only  method  of  effectual  control.  The 
destruction  of  weeds  and  fall  plowing  should  prevent  any  general 
injury.  Usually  the  injury  is  but  local,  and  fortunately  the 
caterpillars  are  attacked  by  numerous  parasites  which  aid  in 
their  control,  sometimes  to  the  extent  of  killing  70  per  cent  of 
them.  In  small  gardens  the  prompt  destruction  of  infested 
plants  will  prevent  the  caterpillars  from  migrating  to  others. 
Where  weeds  are  infested  in  or  near  a  crop  they  should  be  destroyed 
as  soon  as  cut,  for  if  left  on  the  ground  the  larvse  will  promptly 
migrate  to  the  nearest  plants.  Where  fields  are  kept  clean  of 
weeds  there  will  be  little  trouble.* 

Cutworms  f 

Under  the   general   term   cutworms   we   commonly  designate 

any  of  the  larvae  of  several  species  of    moths  which  are  more 

or  less  similar  in  general  appearance  and  habits,  and  which  have 

the  habit  of  feeding  on  low-growing  vegetation,  and  cutting  off 

the  stem  just  at  the  surface  of  the  ground.      They  should  be 

carefully  distinguished  from  white  grubs,   which  are  sometimes 

wrongly  called  cutworms  on  account  of  their  similar  habits.    Some 

*  See  Forbes,  23d  Report  State  Entomologist  of  Illinois,  p.  44;  Washburn, 
12th  Report  State  Entomologist  of  Minnesota,  p.  151;  Journal  Economic 
Entomology,  III,  p.  165;  Smith,  Report  N.  J,  Agr.  Exp.  Sta.  for  1905,  pp. 
584-587. 

t  Various  species  of  the  family  Noctuidce. 


INSECTS  AFFECTING  GRAINS,  GRASSES,  ETC. 


85 


of  the  species  attack  certain  crops  more  commonly  than  others, 
but  most  of  them  are  quite  omnivorous  in  their  feeding.    When 


Fig.  61. — Earth  removed  from  base  of  seedling  to  show  cutworm  in  hiding- 
natural  size. 

they  become  overabundant  they  will  eat  anjrthing  green  and  suc- 
culent— foliage,  flowers,  buds,  fruit,  stalks,  or  roots,  and  sometimes 


Fig.  62. — Greasy  cutworm  {Agrotis 
ypsilon);  a,  larva;  b,  head  of  same; 
c,  adult — natural  size.  (After  How- 
ard, U.  S.  Dept.  Agr.) 


Fig.    63.— The 

worm  (Agrotis  messoria) 
Riley.) 


«; — -J 

dark-sided      cut- 


(After 


86       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


migrate  to  other  fields  in  armies  like  the  army  worms.      Some 
species  commonly  climb  young  fruit  trees  which  have  been  planted 


Fig.  64. — Peridromia  saucia:  a,  adult,  h,  c,  d,  full-grown  larvae,  e,  f,  egg^s; 
all  natural  size  except  e,  which  is  greatly^  enlarged.  (After  Howard 
U.  S.  Dept.  Agr  ) 

on  grassy  land  or  which  are  allowed  to  grow  in  grass  or  weeds 

and  are  known  as  climbing  cut- 
worms. Our  common  species  are 
most  injurious  to  garden  cropsand 
to  corn,  cotton,  tobacco  and  simi- 
lar crops  grown  in  hills  or  rows, 
small  grains  and  forage  crops  be- 
being  injured  but 
rarely. 

Though  over  a 
score  of  species  are 
common,  it  is  not 
practicable  to  dis- 
tinguish them  i  n 
this  discussion,  and 
though   their  life 

Fig.  65. — The  bronzed  cutworm  (IVephelodes  minians  Guen,):  back  and  side, 
views  of  larva — enlarged,  and  moth — natural  size.     (After  Forbes.) 


INSECTS  AFFECTING  GRAINS,  GRASSES,  ETC. 


87 


histories  are  somewhat  different,  they  may  be  considered  as  a 
class. 

The  adults  are  moths  with  dark  fore  wings,  variously  marked 
with  darker  or  lighter  spots  and  narrow  bands  as  shown  in 
Figs.  61-68,  and  with  lighter  hind-wings,  which  are  folded  over 
the  back  when  at  rest.     Like  the  cutworms,  they  feed  at  night. 


i 

n 

r 

1 

~^^^^ 

■^^^^^ 

^^~^     w^w 

'  \ 

a""^"'^  ^ 

y  f  J  'l^^^^^ 

JKk" 

^^B^ 

jf        / 

■'■  '7jHH 

■ 

\ 

j 

„.._.,. 

b 

Fig.  66. — Cutworm  moths:  h,  the  well-marked  cutworm-moth  (Nodua  clan- 
destina  Harris);  the  dingy  cutworm  {Feltia  subgothica  Haworth);  male 
(to)  and  female  (J)  moths.     (After  Slingerland.) 

sipping  the  nectar  from  flowers,  and  are  known  as  owlet 
moths.  The  females  deposit  their  eggs  in  grass  land  or  where 
a  crop  has  been  allowed  to  grow  up  in  grass  and  weeds  in  late 
summer,  laying  them  in  patches  on  the  stems  or  leaves  of  grasses 
or  weeds,  or  on  stones  or  twigs  in  such  places. 

The  little  caterpillars  which  hatch  from  these  eggs  in  August 
and  September  feed  on  the  roots  of  whatever  vegetation  is  avail- 
able until  frost,  going  deeper  as  it  approaches,  and  finally  hollow 
out  small  cells,  in  which  they  curl  up  and  hibernate  until  the  next 


88       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

spring.  The  next  spring  they  are  exceedingly  hungry  after  their 
long  fast,  and  attack  any  vegetation  at  hand  with  surprising  vorac- 
ity. If  the  land  is  in  grass  or  weeds  they  have  plenty  of  food, 
and  if  it  is  then  plowed  and  planted  in  some  crop,  this  will 
certainly  be  injured. 

The  cutworms  usually  become  full  grown  during  late  spring 
or  early  summer,  and  are  then  about  1|  to  2  inches  long,  of 
a  dull  brown,  gray  or  blackish  color,  often  tinged  with  green- 
ish, and  more  or  less  marked  with  longitudinal  stripes,  oblique 
dots  and  dashes,  the  markings  usually  being  of  a  subdued 
tone,  so  that  the  cutworm  harmonizes  in  color  with  the 
soil.  They  are  cylindrical,  with  the  head  and  prothoracic  plate 
horny  and  reddish  brown,  and  bear  three  pairs  of  jointed  legs 


Fig.  67.— Moth  of  the  glassy 
cutworm  {Hadena  devas- 
tatrix  Brace).  (After 
Forbes.) 


Fig.   68. — Granulated  cut-worm    (Agrotis^ 
annexa):  a,  larva;  /,  pupa;  h,  adult — 
natural    size.     (After  Howard,    U.    S. 
Dept.  Agr.) 


on  the  thorax  and  five  pairs  of  prolegs  on  the  abdomen.  The 
mature  caterpillars  pupate  in  cells  a  few  inches  below  the  sur- 
face and  in  three  or  four  weeks  the  adult  moths  emerge,  usually 
in  July  and  early  August  in  the  Central  and  Northern  States 
and  earlier  farther  south. 

Thus  there  is  usually  but  one  generation  a  year  in  the  North 
while  in  the  South  there  are  commonly  two  generations  and  in 
some  cases  three.  Though  other  stages  than  the  larvae  of 
various  species  are  known  to  hibernate  sometimes,  nevertheless 
the  worst  injury  is  usually  done  in  the  spring,  when  young  plants 
have  just  been  set  or  are  just  appearing. 


INSECTS  AFFECTING  GRAINS,  GRASSES    ETC.  89 

Control. — It  is  evident  from  their  life  history  that  like  the 
white  grubs  and  wireworms,  cutworms  may  be  most  effectually 
combated  by  plowing  in  late  fall  and  again  plowing  and  har- 
rowing thoroughly  in  early  spring,  so  as  to  keep  the  land  fallow 
and  thus  starve  them  out.  Land  which  is  to  be  planted  in 
corn  or  crops  subject  to  cutworm  injury  should  be  plowed  as 
early  as  possible  in  late  summer  of  the  preceding  j^ear  and  kept 
fallow  so  that  the  moths  will  not  deposit  their  eggs  upon  it, 
as  they  will  if  it  is  left  in  grass  or  weeds. 

Poisoned  bran  mash  (see  p.  57)  is  probably  the  best  thing 
for  destro3dng  cutworms,  and  if  well  applied  a  few  days  before 
plants  are  set  or  a  few  days  after  seed  is  planted,  will  often 
protect  crops  on  infested  land.  On  corn  land  it  may  be  applied 
with  a  seed  drill,  and  in  gardens  an  onion  drill  is  sometimes 
used  in  the  same  way,  placing  the  mash  on  the  surface  near 
the  plants;  or  it  may  be  applied  by  hand,  placing  a  tablespoonful 
near  each  plant  or  every  2  or  3  feet  in  the  row.  Distribute 
the  mash  late  in  the  afternoon,  so  that  it  will  still  be  moist 
when  the  worms  feed  at  dusk.  Keep  poultry  away  from  fields 
so  treated.  Clover  which  has  been  thoroughly  sprayed  or  dipped 
in  water  containing  one-third  pound  Paris  green  per  barrel  may  be 
used  in  the  same  way,  particularly  along  the  outside  of  fields 
to  be  protected  from  invasion  or  along  borders  of  fields  next  to 
grass. 

Market  gardeners  frequently  protect  cabbage,  tomato  and 
similar  plants  by  knocking  the  bottoms  out  of  tin  cans  or  making 
cylinders  of  building  paper  and  placing  these  around  the  stems, 
sinking  them  into  the  soil.  Where  cutworms  assume  the  climbing 
habit  and  attack  fruit  trees,  distribute  the  bran  mash  or  poisoned 
clover  liberally  around  the  bases  of  the  trees  and  put  a  band 
of  tanglefoot  around  the  trunk  of  each  tree,  which  will  prevent 
their  ascent.  Thorough  cultivation  of  the  orchard  and  neighbor- 
ing land  will  also  reduce  their  numbers.  When  they  assume  the 
migratory  habits  of  army  worms,  they  may  be  controlled  by  the 
same  methods  as  described  for  them.  Garden  plants  may  some- 
times be  protected  from  cutworms,  as  well  as  flea  beetles,  by  dip- 
ping them  in  arsenate  of  lead,  3  pounds  per  barrel,  when  planting. 


90       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Chinch-bug  * 

The  adult  Chinch-bug  is  about  one-fifth  inch  long,  with  a 
black  body.  Its  white  wings  lie  folded  over  each  other  on  the 
abdomen,  and  are  marked  by  a  small  black  triangle  on  their 
outer  margins,  while  the  bases  of  the  antenna?  and  the  legs  are 
red.  The  young  bugs  are  yellowish  or  bright  red  marked  with 
brownish-black,  becoming  darker  as  they  grow  older.  Along 
the  Atantic  coast  and  along  the  southern  shores  of   the  Great 


Fig.  69. — Areas  in  the  United  States  over  which  the  chinch-bug  occurs  in  most 
destructive  numbers.  (After  Webster,  Dept.  Agr.,  Farmer's  Bulletin 
657.) 

Lakes  north  of  a  line  from  Pittsburg,  Pa.,  to  Toledo,  Ohio,  the 
majority  of  the  adults  have  short  wings  reaching  but  half  over  the 
abdomen  and  are  incapable  of  flight;  but  between  the  Alleghany 
and  Rocky  Mountains  the  long-winged  form  greatly  predominates. 
It  occurs  also  in  restricted  localities  in  Central  America  and 
along  the  Pacific  coast.  The  worst  injury  is  to  small  grains 
and  corn  in  the  Central  and  North  Central  States,  but  frequently 
injury  is  done,  in  the  Eastern  States  especially,  to  timoth}^  meadows 
which  have  stood  for  several  years.  Though  individually  insig- 
*  Blissus  leucopterus  Say.     Family  LijgceidcE. 


INSECTS  AFFECTING  GRAINS,  GRASSES,  ETC. 


91 


nificant,  when  assembled  in  countless  myriads  chinch-bugs  have 
doubtless  been  of  greater  injury  to  the  farmers  of  the  Mississippi 
Valley  than  almost  any  other  insect  attacking  grain  crops,  the  total 
damage  from  1850  to  1909  being  estimated  at  $350,000,000.* 

Life  History. — During  the  winter  the  bugs  hibernate  in  clumps 
of  grass,  in  corn  butts,  and  in  old  shocks  of  corn,  or  under  what- 
ever rubbish  is  available.  In  early  spring  they  assemble  in 
fields  of  grass  and  small  grains.  Soon  they  pair  and  the  females 
commence  to  lay  their  small  yellowish-white  eggs  upon  the 
roots  or  bases  of  the  stalks,  each  laying;  some  150  to  200  eggs. 


Fig.  70. — The  chinch-bug  {Blissus  leucopterus  Say):  adult  at  left;  a,  b,  eggs 
magnified  and  natural  size;  c,  young  nymph;  e,  second  stage  of  nymph; 
/,  third  stage;  g,  full-grown  nymph  or  pupa;  d,  h,  j,  legs;  i,  beak  through 
which  the  bug  sucks  its  food.     (After  Riley.) 

The  eggs  are  laid  from  the  middle  of  April  until  the  first  of 
June,  depending  upon  the  latitude  and  weather,  and  hatch  in 
two  or  three  weeks.  As  the  nymphs  grow  they  often  do  serious 
injury  to  small  grains  and  grass,  upon  which  they  become  full 
grown  about  the  time  of  harvest.  When  wheat  is  harvested 
they  spread  to  oats  and  soon  to  corn,  but,  curiously  enough,  though 
the  adults  have  wings  they  travel  from  field  to  field  on  foot,  were  it 
not  for  which  fact  we  should  be  at  a  loss  to  cope  with  their  migra- 
tion. Eggs  are  now  laid  upon  the  unfolding  leaves  of  the  corn, 
from  which  the  njTiiphs  commence  to  emerge  in  about  ten  days. 
This  second  brood  matures  on  corn  in  August  and  September  and 
is  the  one  which  later  hibernates  over  winter,  though  where  corn 
is  not  available  the  whole  season  may  be  passed  on  grass. 

*  See  Circular  113,  Bureau  Entomology,  U.  S.  Dept.  Agr.,  F.  M.  Webster, 
and  Headlee  and  McColloch,  Kansas  Expt.  Sta.  Bulletin  No.  191. 


92       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Control. — The  burning  over  of  grass  land,  and  the  grass  along 
fences,  hedges,  and  roads,  as  soon  as  it  becomes  dry  enough  in 
late  fall  and  early  winter,  is  of  prime  importance  to  destroy 
the  bugs  after  they  have  gone  into  hibernation.  The  removal 
of  all  corn  stalks  from  the  fields  and  plowing  the  butts  under 


Fig.  71. — Seasonal  cycle  of  the  chinch-bug.     (From  Headlee  and  McCoUoch.) 

deeply,  or  where  the  bugs  are  very  abundant,  raking  out  the 
butts  and  burning  them,  will  help  rid  the  fields  of  the  pest. 

It  is  practically  impossible  to  combat  the  pest  in  the  summer 
on  grass  or  small  grains,  but  its  migration  to  corn  or  from  field 
to  field  may  be  effectually  checked.  In  dry  weather  a  dust 
furrow  may  be  used  as  a  barrier  to  good  advantage.  Just  before 
harvest  plow  a  deep  furrow  around  the  field  to  be  protected, 
or  on  the  threatened  sides,  and  thoroughly  pulverize  the  soil  by 


JS.^Dusty-furrow-  trap. 

FiQ.  72. — Barriers  for  chinch-bugs,  showing  methods  of  construction.     (U.  S. 
D,  A.  Bureau  of  Entomology.)  93 


94         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

dragging  a  heavy  log  back  and  forth  in  the  furrow,  making 
the  side  next  the  corn  as  steep  as  possible.*  In  attempting 
to  climb  this  barriar,  the  dust  will  slide  from  under  the  bugs 
and  large  numbers  will  accumulate  in  the  bottom  of  the  furrow, 
where  they  will  be  killed  by  the  heat  of  the  soil  if  it  has  a 
temperature  from  110°  to  120°  (air  temperature  of  over  90°). 
Keep  the  furrow  clean  by  dragging  a  log  through  it  now  and 
then.  Sink  post-holes  a  foot  deep  every  few  feet  in  the  bottom 
of  the  furrow  and  the  bugs  will  collect  in  them  and  may  be 
crushed  or  killed  with  kerosene.  Such  a  dust  furrow  will  be 
of  no  value  in  showery  weather,  and  is  most  effective  in  hot  dry 
weather  on  light  soil;  it  may  often  be  used  to  advantage  in  com- 
bination with  the  following  methods. 

In  place  of  the  dust  furrow  or  in  combination  with  it,  a  strip 
of  coal  tar  is  often  run  around  the  field.  The  strip,  which  should 
be  about  the  size  of  one's  finger,  can  be  made  by  pouring 
from  a  watering  can  with  the  mouth  stopped  down,  and  should 
be  run  inside  the  dust  furrow  and  with  post-holes  sunk  along 
its  outer  edge.  Sometimes  it  is  run  in  a  zig-zag  line  with  the 
holes  at  the  inner  angles  so  that  the  bugs  will  be  concentrated 
at  the  holes.  These  tar  strips  must  be  freshened  whenever  dust 
or  rubbish  covers  them.  The  soil  may  be  prepared  for  the  tar 
strip  by  plowing  a  back  furrow  and  packing  the  top  with  a  roller 
or  beating  it  hard  with  spades;  or  a  strip  of  sod  may  be  prepared 
by  scraping  away  the  grass  with  a  farm  scraper  and  then  smooth- 
ing carefully  with  shovels  or  hoes;  or  a  dead  furrow  may  be  run 
and  the  tar  strip  run  on  the  smooth  bottom.  To  maintain  such  a 
tar  strip  for  four  weeks  costs  about  $2  a  mile  and  has  proven 
itself  entirely  practical  and  effective. 

if  the  bugs  have  already  become  numerous  in  the  outer  rows  of 
corn,  most  of  them  may  be  destroyed  by  spraying  with  kerosene 
emulsion  (see  p.  44)  made  to  contain  four  per  cent  kerosene,  apply- 
ing it  in  the  early  morning  or  towards  night.  It  costs  65  cents  a 
barrel  diluted,  and  a  man  will  spray  five  acres  per  day,  using  a 

,  ,*Such  a  furrow'may  possibly  be  made  more  readily  by  plowing  several 
iurrows  and  harrowing  the  ground  thoroughly  until  reduced  to  a  fine  mulch 
and  then  plowing  a  dead  furrow  through  the  middle,  and  then  dragging  this 
with  a  log,  making  the  sides  as  steep  as  possible.  With  such  construction 
the  furrow  will  cost  about  five  cents  per  linear  rod. 


INSECTS  AFFECTING    GRAINS,    GRASSES,  ETC.  95 

barrel  per  acre.  Whale-oil  soap,  one-half  pound  to  the  gallon  of 
water,  has  proven  equally  effective  and  cost  $2.00  per  barrel. 

A  blast  torch,  for  which  an  attachment  is  furnished  with 
many  of  the  compressed-air  sprayers,  may  be  used  to  advantage 
for  destrojdng  the  bugs  in  a  dust  furrow  or  along  the  tar  line, 
or  a  spray  of  pure  kerosene  or  crude  petroleum  may  be  used  for 
the  same  purpose. 

Extensive  experiments  have  been  made  in  Illinois  and  Kansas 
with  the  use  of  the  muscardine  fungus  *  against  the  chinch-bug. 
Though  occasionally  the  results  seem  to  be  profitable,  and  though 
it  is  undoubtedly  effective  in  wet  seasons  and  it  may  be  well 
to  distribute  the  fungus  to  places  where  it  does  not  occur  so 
that  it  may  reduce  the  numbers  of  the  bugs  in  wet  seasons,  it 
seems  to  be  of  very  little  value  in  dry  seasons,  when  the  injury 
is  worst,  and  cannot  be  relied  upon  to  check  the  increase  of  the 
pest  when  used  according  to  the  methods  so  far  devised. 

When  chinch-bugs  become  abundant  and  their  migration  to 
corn  seems  imminent,  the  farmer  should  prepare  to  devote  himself 
and  as  many  hands  as  necessary  to  fighting  them  until  their 
advance  is  checked,  for  delay  will  mean  ruin,  while  the  prompt 
use  of  the  above  methods  will  save  the  corn  crop. 

Grasshoppers  or  Locusts  f 

Plagues  of  destructive  locusts  —  or  what  we  Americans  call 
grasshoppers  —  have  been  recorded  since  the  dawn  of  history. 
In  America  the  worst  devastation  was  done  by  the  flights  of 
the  Rocky  Mountain  or  Migratory  Locust  (Melanoplus  spretus 
Thos.),  which  swooped  down  upon  the  States  of  the  western 
part  of  the  Mississippi  Valley  in  the  years  1873  to  1876  in  destruc- 
tive clouds. 

The  Rocky  Mountain  Locust 

Let  us  first  consider  the  species  which  has  been  the  most 
injurious,  as  the  other  locusts  differ  from  it  in  but  few  essential 
points  other  than  in  being  non-migratory. 

To  understand   correctly  its  habits  the  reader  should   first 

divide  the  area  which  this  species  affected  into  three  parts.     Of 

*Sporoirichum  globuliferum. 

t  Various  species  of  the  family  Acrididoce.  See  W.  R.  Walton,  Farmers' 
Bulletin  747,  U.  S.  Dept.  Agr. 


96         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

these  (1)  the  Permanent  Region,  which  included  the  highlands  of 
Montana,  Wyoming,  and  Colorado,  formed  the  native  breeding- 
grounds,  where  the  species  was  always  found  in  greater  or  less 
abundance;*  (2)  the  Subpermanent  Region,  which  included  Man- 
itoba, the  Dakotas,  and  western  Kansas,  was  frequently  invaded; 
here  the  species  might  perpetuate  itself  for  several  years,  but 
disappeared  from  it  in  time;  (3)  the  Temporary  Region,  which 
included  the  States  bordering  the  Mississippi  River  on  the  west, 
was  that  only  periodically  visited  and  from  which  the  species 
generally  disappeared  within  a  year. 

Spread — When  for  various  reasons  the  locusts  became  excess- 
ively abundant  in  the  Permanent  Region  they  spread  to  the 
Subpermanent  Region,  and  from  there  migrated  to  the  Tem- 
porary feeding-grounds.  It  was  the  latter  area  which  suffered 
most  severely  from  their  attacks,  but,  fortunately,  they  did 
not  do  serious  injury  the  next  year  after  a  general  migration. 
In  the  Subpermanent  Region  their  injuries  were  more  frequent 
than  in  the  Temporary,  but  were  hardly  as  severe  or  sudden  as 
farther  east.  Migrating  from  their  native  haunts,  flights  of 
the  grasshoppers  usually  reached  southern  Dakota  in  early  sum- 
mer, Colorado,  Nebraska,  Minnesota,  Iowa,  and  western  Kansas 
during    midsummer,    and    southeastern    Kansas    and    Missouri 


Fig.  73. — Rocky  Mountain  locust;  adult  and  different  stages  of  growth  of 
young.     (After  Riley.) 

during  late  summer,  appearing  at  Dallas,  Texas,  in  1874,  and  about 
the  middle  of  October,  and  even  later  in  1876.  As  thus  indi- 
cated, the  flights  were  in  a  general  south  to  southeasterly  direction, 
while  west  of  the  Rockies  they  descended  to  the  more  fertile 
valleys  and  plains,  but  without  any  such  regularity  as  eastward. 
While  the  rate  of  these  flights  was  variable  and  entirely  dependent 
upon  local  weather  conditions,  twenty  miles  per  day  was  con- 
*  Bull.  25,  U.  S.  Dept.  Agr.,  Div.  Entomology.     C.  V.  Riley. 


INSECTS  AFFECTING    GRAINS,    GRASSES,  ETC.  97 

sidered  a  fair  average.  The  flights  were  more  rapid  and  more 
distance  was  covered  in  the  early  part  of  the  season,  when,  while 
crossing  the  dry  prairies,  a  good  wind  often  enabled  them  to  cover 
200  to  300  miles  in  a  day.  As  they  first  commenced  to  alight  in 
their  new  feeding-grounds  their  stay  was  limited  to  but  two  or 
three  days,  but  later  in  the  season  it  was  considerably  lengthened, 
and,  after  a  section  was  once  infested,  swarms  were  seen  to  be 
constantly  rising  and  drop]3ing  during  the  middle  of  the  day. 

Life  History. — Over  all  the  infested  area,  and  while  still  sweep- 
ing it  bare  of  crops  and  vegetation,  the  females  commence  to  lay 
their  eggs,  and  continue  to  deposit  them  from  the  middle  of  August 
until  frost.     For  this  purpose  ''  bare  sandy  places,  especially  on 


Fig.  74. — Rocky  Mountain  locusts:  a,  a,  a,  females  in  different  positions, 
ovipositing;  b,  egg-pod  extracted  from  ground,  with  end  broken  open;  c, 
a  few  eggs  lying  loose  on  ground;  d,  e,  showed  the  earth  partially  removed, 
to  illustrate  an  egg-mass  already  in  place  and  one  being  placed;/,  shows 
where  such  an  egg-mass  has  been  covered  up.     (After  Riley.) 

high,  dry  ground,  which  is  tolerably  compact  and  not  loose,"  are 
preferred.  "  INIeadows  and  pastures  where  the  grass  is  closely 
grazed  are  much  used,  whOe  moist  or  wet  ground  is  generally 
avoided." 

In  such  places  the  female  deposits  her  eggs  in  masses  of  about 
thirty.  These  are  placed  about  an  inch  below  the  surface  in 
a  pod-like  cavity,  which  is  lined  and  the  eggs  are  covered  by  a 
mucous  fluid  excreted  during  oviposition.  From  two  to  five  hours 
are  required  for  this  operation,  and  an  average  of  three  of  these 
masses  is  deposited  during  a  period  of  from  six  to  eight  weeks. 


98         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

As  the  time  of  ovipositing  varies  with  the  latitude,  so  the 
hatching  of  the  eggs  occurs  from  the  middle  or  last  of  March 
in  Texas  till  the  middle  of  May  or  first  of  Jime  in  Minnesota 
and  Manitoba.  Until  after  the  molt  of  the  first  skin,  and  often 
till  after  the  second  or  third  molt,  the  young  nymphs  are  con- 
tent to  feed  in  the  immediate  vicinity  of  their  birth.  When 
the  food  becomes  scarce  they  congregate  together  and  in 
solid  bodies,  sometimes  as  much  as  a  mile  wide,  march  across 
the  country,  devouring  every  green  crop  and  weed  as  they  go. 
During  cold  or  damp  weather  and  at  night  they  collect  under 
rubbish,  in  stools  of  grass,  etc.,  and  at  such  times  almost  seem 
to  have  disappeared;  but  a  few  hours  of  sunshine  brings  them 
forth,  as  voracious  as  ever.  When,  on  account  of  the  immense 
numbers  assembled  together,  it  becomes  impossible  for  all  to 
obtain  green  food,  the  unfortunate  ones  first  clean  out  the  under- 
brush and  then  feed  upon  the  dead  leaves  and  bark  of  timber- 
lands,  and  have  often  been  known  to  gnaw  fences  and  frame 
buildings.  Stories  of  their  incredible  appetites  are  legion;  a 
friend  informs  me  that  he  still  possesses  a  rawhide  whip  which 
they  had  quite  noticeably  gnawed  in  a  single  night ! 

As  the  njnnphs  become  full  grown  they  are  increasingly 
subject  to  the  attacks  of  predaceous  birds  and  insects,  insect 
parasites,  fungous  and  bacterial  diseases,  and  are  also  largely 
reduced  by  the  cannibalistic  appetites  of  their  own  numbers. 
When  the  mature  nymphs  transform  to  adult  grasshoppers  and 
thus  become  winged,  large  swarms  are  seen  rising  from  the 
fields  and  flying  toward  their  native  home  in  the  Northwest. 
This  usually  takes  place  during  June  and  early  July  in  the  North, 
and  as  early  as  April  in  Texas,  so  that  it  is  frequently  impos- 
sible to  distinguish  the  broods  of  the  temporary  region  from  the 
incoming  brood  which  has  migrated  from  the  permanent  region. 
Although  the  eggs  for  a  second  brood  are  sometimes  laid,  these 
seldom  come  to  maturity,  and  the  species  is  essentially  single- 
brooded. 

The  Lesser  Migratory  Locust 

Besides  the  Rocky  Mountain  locust  there  is  only  one  other 
species  that  truly  possesses  the  habit  of  migrating,  though  to 
a  far  lesser  extent,  and  which  is  therefore  known  as  the  Lesser 
Migratory  Locust  {Melanoplus  atlantis  Riley).     It  is  considerably 


INSECTS  AFFECTING    GRAINS,    GRASSES,   ETC.  99 

smaller  than  its  western  relative  and  somewhat  resembles  the 
red-legged  locust  both  in  size  and  appearance.  The  species 
is  very  widely  distributed,  occurring  from  Florida  to  the  Arctic 
Circle  east  of  the  Mississippi,  and  on  the  Pacific  slope  north  of 
the  fortieth  parallel  to  the  Yukon.  The  habits  and  life  history 
of  the  species  are  in  all  essentials  practically  the  same  as  the 
former  species,  except  that  they  have  no  particular  breeding- 
grounds.  Injuries  bj'-  this  grasshopper  were  first  noticed  in 
1748,  almost  seventy-five  years  before  the  first  record  of  the 
Rocky  Mountain  locust,  and  since  then  it  has  done  more 
or  less  serious  damage  in  some  part  of  the  territory  inhabited 

every  few  years. 

Non-Migratory  Locusts 

There  are  several  species  of  locusts  which,  though  lacking 
the  migratory  habit,  and  thus  being  more  easily  controlled, 
often  become  so  numerous  as  to  do 
serious  damage  over  limited  areas. 
Both  as  regards  the  regions  inhab- 
ited, and  its  habits,  life  history,  the  ^        .rr       t^   i    i        ,     i 

'  '  -"  Fig.     75.  —  Red  -  legged     locust 

common  Red-legged  Locust  {AI elan-  (Melanoplus  femur-rubrum 
oplus  femur-rubrum  Har.)  hardly  dii-      Harr.).     (After  Riley.) 

f ers  from  the  last  species,  and  is  often  found  in  company  with 
it.  It  is  non-migratory,  however,  and  though  the  damage  it 
does  is  thus  entirely  local,  it  is  often  of  considerable  importance. 

Records  of  locust  plagues  in 
California  date  back  as  far  as 
1722.     Many   of    them    were 
doubtless  due  to  the  California 
Devastating  Locust   (Melano- 
plus devastator  Scud.),  and  in 
the  last  invasion  of  1885  this 
species  outnumbered  all  others 
seven  to  one.     Resembling  the 
last   two   species  in  size  and 
markings,   the  habits  and  life 
Fig.  76. — The  pellucid  locust  {Camnula  history  of  this  species  are  also 
pellucida  Scud.).     (After  Emer ton.)     supposed  to  be  similar  to  them, 
though  they  have  not  as  yet  been  thoroughly  studied. 

Together  with  the  last  species  the  Pellucid  Locust  {Camnula 
pellucida  Scud.)  has  been  largely  responsible  for  the  losses  occa- 


100        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


sioned  by  locusts  in  California,  and  has  also  been  found  in  New 
England,  but  is  not  noted  there  as  especially  destructive. 

Our  largest  winged  American  Locust,  the  American  Acridium 
(Schistocerca  americana  Scud.),  is  practically  confined  to  the 
Southern  States  from  the  District  of  Columbia  to  Texas,  and 
thence  south  through  Mexico  and  Central  America,  being  rarely 
found  in  the  North.  This  species  is  essentially  a  tropical  one, 
and  has  often  been  exceedingly  destructive,  being  especially  so 
in  1876  in  Missouri,  Tennessee  North  Carolina,  Georgia,  and 
southern  Ohio. 

Considerably  larger  than  the  preceding  species  are  the  Dif- 
ferential Locust  {Melanoplus  differentialis  Thos.)  and  the  Two- 


Fig.  77. — The  American  acridium    (Schistocerca  americana  Scud.).     (After 

Riley.) 

striped  Locust  {Melanoplus  hivittatus  Scud.), 'of  which  the  former 
is  peculiar  to  the  central  states  of  the  Mississippi  Valley,  Texas, 
New  Mexico,  and  California,  while  the  latter  has  a  more  extended 
range  from  Maine  to  Utah  and  as  far  south  as  Carolina  and 
Texas.       These  two   differ  from  the  smaller  species  in  laying 

only  one  or  two  masses  of 
eggs,  and  the  eggs  of  dif- 
ferentialis have  often  been 
found  placed  under  the  bark 
of  logs,  but  otherwise  their 
"^^  ""  ""^^^^^  ''=*«^    habits    are     very    similar. 

Fig.  78.— The  Two-striped  locust  (Mela-  The  two-striped  locust  is 
jioplusUvittatus  Scud.).  (After  Riley.  characterized  by  two  yel- 
lowish stripes  extending  from  the  eyes  along  the  sides  of  the 
head  and  thorax  to  the  extremities  of  the  wing-covers,  and  is 
probably  the  species  most  commonly  observed  by  the  farmer. 


INSECTS  AFFECTING    GRAINS,    GRASSES,  ETC.  101 


The  Differential  Locust. — Throughout  the  Mississippi  Valley 
from  Illinois  southward,  the  Differential  Locust  is  one  of  the  most 


Fig.  79. — The  differential  locust  (Mclanoplus  differentials  Thos.).     (After 

Riley.) 

common  and  destructive  grasshoppers,  and  is  an  excellent  example 
of  several  of  our  more  abundant  and  injurious  species  which  have 
very  similar   habits. 


Fig.  80. — The  southern  lubber  grasshopper  (DicUjophorus  reticulatus) :  nymph 
and  adult,  slightly  enlarged. 

The    little    grasshoppers    hatch    about    the   middle  of   May, 
from  eggs  which  were  laid   in    the  fall,  though  we  have  observed 

them  in  March  in  Central  Texas,  and 
are  of  a  dusky  brown  color,  marked 
with  yellow.  The  head  and  legs  are 
the  most  prominent  feature  of  the 
young  nymphs.  During  their  sub- 
sequent growth  they  molt  five  times 
at  intervals  of  ten  days  to  two  weeks,  the  relative  size  and  ap- 
pearance of  the  different  stages  being  shown  in  Fig.  82. 


Fig.     81. —  Egg-mass  of  the 
differential  locust — enlarged. 


102         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  hoppers  become  full  grown 
.bout    the  first   of   July.     The 
adult  is  about  1^  inches  long,  its 
wings  expand  2|  inches,  and  it 
is  of    a  bright    yellowish-green 
color.     The  head  and  thorax  are 
olive-brown,  and  the  front  wings 
are  of  much  the  same  color,  with- 
out other  markings,  but  with  a 
brownish  shade  at  the  base;  the 
hind-wings  are  tinged  with  green; 
the  hind-thighs  are  bright  yellow, 
especially  below,  with  four  black 
marks;  the  hindshanks  are  yellow 
with  black  spines  and  a  ring  of 
the  same    color  near  the  base. 
The  adults  at  once  attack  what- 
ever crops    are   available,    often 
finishing  the  destruction  of  those 
injured  by  them  as  nymphs,  but 
in  a  few  days  their  appetites 
seem  to  become  somewhat 
appeased    and     they    com- 
mence to  mate  and  wander 
in  search  of  suitable  places 
for  laying  the  eggs.      Rela- 
tively few  eggs  are  laid  in 
cultivated  ground, the  favor- 
ite   places   being   neglected 
fields  grown  up  in  grass  and 
weeds,  the   edges   of  culti- 
vated  fields,  private  road- 
ways, banks  of  ditches  and 
small  streams,  and  pasture 
lands.     Alfalfa  land  is  a  fa- 
vorite place  for  oviposition, 
and     alfalfa   is    frequently 

•^^?-  8?;— Nymphs  of  the  differential  locust  seriously    injured    by    this 
m  different  stages   (1  to  5)  of  growth—  .  t^  •     i      wi         i 

all  enlarged.  species.     It  is  doubtless  due 


INSECTS  AFFECTING    GRAINS,    GRASSES,  ETC. 


103 


to  these  egg-laying  habits  and  the  abundance  of  food  on  unculti- 
vated land  that  this  species  always  increases  enormously  on  land 
which  has  been  flooded  and  then  lies  idle  for  a  year  or  two. 


Fig.  83. — A  Locust-mite  {Tromhidium  locustarum) :  a,  the  larva  as  seen  on 
locust's  wing;  c,  male  mite;  d,  female,  the  two  latter  appearing  as  when 
egg-destroyers — all  greatly  enlarged.     (After  Riley.) 

Most  of  the  eggs  are  laid  in  August  and  early  September.  Each 
female  deposits  a  single  egg  mass  of  about  100  eggs  just  beneath 
the  surface  of  the  soil.  During  this  season  the  females  may 
frequently  be  found  with  the  abdomens  thrust  deep  in  the 
soil,  as  the  process 
of  egg-laying  re- 
quires some  time. 
The  eggs  are  yellow 
and  arranged  irre- 
gularly in  a  mass 
which  is  coated 
with  a  gluey  sub- 
stance to  which  the 
earth  adheres, 
which  protects 

them  from  variable  ^     ^^      .   „        •  ,  n     ■, 

.      Pig. 84. — A nmom?/to  egg-parasite,     a,  ily,  o,  puparium; 
conditions  ol  mois-  c,  larva;  d,  head  of  larva.     (After  Riley.) 

ture  and  temperature. 

Enemies. — As  before  mentioned,  large  numbers  of  the  nymphs 

are  destroyed  before  reaching  maturity  by  their  natural  enemies. 

Among  these  a  minute  fungus  undoubtedly  kills  many  of  those 

already  somewhat  exhausted,  especially  during  damp  weather. 


104       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Almost  all  of  our  common  birds,  as  well  as  many  of  the  smaller 
mammals,  are  known  to  feed  quite  largely  upon  them. 

A  small  red  mite  {Tromhidium  locustarum  Riley),   somewhat 


Fig.   85. — ^Two   tachina-flies.     (Exorista   Icucaniae   Kirk,    and   E.  flavicauda 
Riley.)     (After  Riley.) 

resembling  the  common  red  spider  infesting  greenhouses,  is 
often  of  great  value  not  only  in  killing  the  nymphs  by  great 
numbers  of  them  sucking  out  the  life-juices  of  the  young  hopper, 
but  also  in  greedily  feeding  upon  the  eggs. 

The  maggots  of  several  species 
of  Tachina-flies  are  of  consider- 
able value  in  parasitizing  both 
nymphs  and  adult  locusts. 
Their  eggs  are  laid  on  the  neck 
^1  of  a  locust,  and,  upon  hatching, 
the  maggots  pierce  the  skin  and 

Fig.    86.— Common  flesh-fly    (Sarco-  live  inside  by  absorbing  its  juices 
phaga  carnaria  Lmn.j:    a,  larva;  b, 

pupa;  c,  fly.  Hair-lines  show  natural   and    tissues.      When   full  grown 

size.  _(After  Riley.)  the    maggots    leave  the    locust, 

descend  into  the  earth,  and  there  transform  to  pupae  inside  of  their 

cast  skins,  and  from  the  pupse  the  adult  flies  emerge  in  due  time. 

The  maggots  of  one  of  the  Bee-flies    {Systcechus  oreas)  feed 

upon  grasshopper  eggs,  but  their  life  history  is  not  fully  known. 

The  common  Flesh-fly  (Sarcophaga  carnaria  Linn.),  Fig.  86,  is 

also  very  destructive,  though  largely  a  scavenger. 

But  of  all  the  insects  attacking  locusts,  the  Blister-beetles, 
which,  unfortunately,  are  often  known  to  us  as  very  injurious 
to  various  garden  crops,  are  probably  of  the  most  value.  The 
female  beetle  deposits  from  four  to  five  hundred  of  her  yellov/ish 
eggs  in  irregular  masses  in  loose  ground,  and  in  about  ten  days 


INSECTS    AFFECTING    GRAINS,    GRASSES,  ETC. 


105 


there  hatch  from  these  eggs  some  "  very  active,  long-legged  larvae, 
with  huge  heads  and  strong  jaws,  which  run  about  everywhere 
seeking  the  eggs  of  locusts."  Each  of  these  larvse  will  consume 
one  of  the  masses  or  about  thirty  eggs.  The  subsequent  life  his- 
tory of  these  insects  is  very  complicated  on  account  of  their  pecu- 
liar habits,  but  the  various  stages  are  shown  in  Fig.  87. 

Control. — As  the  eggs  are  usually  laid  in  the  ground  in  the 
fall,  deep  plowing  in  late  fall  or  early  spring  effectuallv  buries 


(^^^i.aa^a,      ...i^-      e^^^      ffJiXTo^       ^"^^ 

Fig.  87. — Various  stages  of  a  blister-beetle  (Epicauta  vittata).     (After  Riley.) 

them  too  deep  for  the  young  nymphs  to  emerge.  On  alfalfa 
land  thorough  disking  is  often  used  for  the  same  purpose. 
Thorough  harrowing  in  the  fall  so  as  to  pulverize  the  soil  for 
the  depth  of  an  inch  will  break  up  many  of  the  egg  masses, 
though  it  is  not  as  sure  a  control  as  plowing  them  under. 

When  the  young  emerge,  they  may  sometimes  be  destroyed 
by  burning  over  stubble,  grass  and  rubbish  where  it  is  present 
in  sufficient  quantities,  or  by  augmenting  it  with  straw,  which 
may  be  done  to  advantage  on  cold  days  when  the  nymphs  are 
congregated  in  such  shelter.  If  the  surface  of  the  ground  is 
smooth  and  hard  many  may  be  killed  by  the  use  of  a  heavy 
roller,  particularly  in  the  morning  and  evening,  when  they  are 
sluggish  in  their  movements.  Plowing  a  badly  infested  field 
in  a  square,  working  toward  the  centre  so  as  to  drive  the  young 
nymphs  inward,  will  result  in  burying  many  of  them  in  the  furrows, 
and  the  last  may  be  burned  or  trapped  in  holes  as  described 
below.  Simple  ditches  2  feet  wide  and  2  feet  deep  form 
effectual  barriers  for  the  young  hoppers.  The  sides  next  to  the 
crop  to  be  protected  should  be  kept  finely  pulverized  by  hauling 
a  log  or  a  brush  of  dead  branches  through  the  ditch.  The  ditch 
may  be  made  as  described  for  chinch-bugs  and  is  handled  in 
the  same  manner,  the  little  hoppers  drifting  to  the  bottom  of 
the  ditch,  where  they  are  killed  by  the  heat  on  a  hot  day  or 


Fig.  88. — Two  hopperdozers,  tied  together,  at  work.     (After  Lugger,  Bull.  43, 
(Minn.  Agr.  Exp,  Sta.) 

106 


INSECTS   AFFECTING    GRAINS,    GRASSES,  ETC.         107 

where  they  are  caught  in  post-holes  sunk  every  few  feet  in  the 
bottom  of  the  ditch.  This  method  may  be  used  to  advantage 
in  plots  of  corn,  cotton,  or  garden  truck  which  has  already 
become  infested,  by  running  furrows  around  the  field  and  occa- 
sionally through  it,  and  then  driving  the  young  hoppers  toward 
them,  which  may  be  readily  done  by  a  number  of  children  armed 
with  branches.  Where  ditches  containing  water  are  available 
the  j^oung  hoppers  may  be  very  effectively  destroyed  by  oiling 
the  surface  of  the  water  with  kerosene  emulsion  and  then  driving 


Fig.  89. — Hopperdozer  with  cloth  back,  showing  construction.     (After  W.  R. 
Walton,  Farmers'  Bulletin  747,  U.  S.  Dept.  of  Agriculture.) 

them  into  the  ditches,  for  even  if  they  succeed  in  crawhng  out 
they  will  succumb  to  the  oil. 

In  pastures,  small  grains  or  any  crops  permitting  their  use, 
immense  numbers  of  the  nymphs  maj^  be  caught  by  the  use 
of  hopperdozers,  which  may  be  utihzed  where  the  use  of  poisoned 
bran  would  not  be  possible.  The  hopperdozer  consists  of  a 
shallow  pan  containing  water  with  a  surface  of  kerosene,  crude 
petroleum,  or  coal  tar,  which  is  sometimes  used  without  water. 
The  pan  is  mounted  on  runners  or  wheels  and  if  larger  than  about 
3  feet  square  is  usually  provided  with  partitions  to  prevent 
slopping.  The  back  and  sides  are  high  and  sometimes  are  made 
of  canvas.  "A  good  cheap  pan  is  made  of  ordinary  sheet  iron, 
8  feet  long,  11  inches  wide  at  the  bottom,  and  turned  up  a  foot 


108 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


high  at  the  back  and  an  inch  high  in  front.  A  runner  at  each 
end,  extending  some  distance  behind,  and  a  cord  attached  to  each 
front  corner,  complete  the  pan.  We  have  known  of  from  seven 
to  ten  bushels  of  young  locusts  caught  with  one  such  pan  in  an 
afternoon.  It  is  easily  pulled  by  two  boys,  and  by  running 
several  together  in  a  row,  one  boy  to  each  rope,  and  one  to  each 
contiguous  pair,  the  best  work  is  performed  with  the  least  labor." 
Larger  pans  are  drawn  or  pushed  by  horses.  The  oil  is  best 
used  on  the  surface  of  water,  from  which  the  insects  are  removed 
with  a  strainer,  and  any  which  hop  out  will  die  after  having  come 
in  contact  with  the  oil. 

Destroying  the  Adults. — The  destruction  of  the  winged  insects 
is  an   entirely  hopeless  task,   for,   though   even   large  numbers 


Fig,  90. — ^The  Price  oil-pan   or  hopperdozer,  with    partitions  to  prevent 
slopping.     (After  Riley.) 

are  caught,  so  many  will  remain  that  the  damage  done  the 
crops  would  be  but  very  slightly  diminished.  One  of  the  most 
promising  means  for  preventing  the  swarms  of  winged  migratory 
locusts  from  alighting  in  the  fields  is  by  a  dense  smudge,  in 
which  some  foul-smelling  substances  are  placed.  Where  strictly 
attended,  and  with  favorable  winds,  this  has  often  proved  highly 
successful.  To  accomplish  the  best  results  farmers  over  an 
extensive  area  should  combine  in  its  use. 


INSECTS   AFFECTING  GRAINS,   GRASSES,  ETC.  109 

The  South  African  Fungus. — In  1900  Professor  Morgan  made  a 
test  of  a  fungous  disease  which  had  been  found  to  destroy  large 
numbers  of  grasshoppers  in  South  Africa,  to  determine  whether, 
after  starting  it  by  artificial  propagation,  it  would  spread  suffi- 
ciently to  destroy  any  considerable  number  of  locusts  The 
weather  was  favorable,  rains  being  frequent.  Early  in  August 
it  was  found  that  "  over  the  areas  where  the  liquid  infection 


^^i 


Fig.  91. — Carolina  locust  killed  by  fungous  disease.     (Photo  by  Weed.) 

was  spread  diseased  hoppers  were  abundant."  "As  many  as 
a  dozen  dead  grasshoppers  could  be  found  upon  a  single  plant, 
and  some  upon  nearly  every  weed  on  ditch-banks  where  grass- 
hoppers were  numerous.  From  the  centres  of  infection  great 
areas  had  become  inoculated,  spreading  even  beyond  the  planta- 
tions first  infected."  The  property  upon  which  it  was  placed 
became  thoroughly  infected  with  the  fungus.  Strangely,  though 
many  other  species  of  grasshoppers  were  abundant,  only  the 
differential  locust  was  killed  by  it.  Dr.  Howard  states  that  this 
disease  has  also  spread  and  done  effective  work  in  Colorado. 
However,  more  recent  experiments  made  by  the  writer  in  Texas 
gave  only  negative  results,  and  it  is  doubtful  if  any  reliance  can 
be  placed  upon  the  artificial  use  of  such  fungous  diseases  for 
locust  control. 

Poisoning. — ^A  mash  composed  of  bran,  molasses,  water,  and 
some  form  of  arsenic,  flavored  with  fruit  juice  according  to  formula 
given  on   page  57,   has  been  extensively  used  for  grasshoppers 


110       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


especially  during  the  outbreaks  of  more  recent  years  in  Kansas 
and  neighboring  states.  Preparation  of  the  poison  is  frequently 
under  the  direction  of  the  county  agent  and  the  Experiment  Station 
representatives  and  the  distribution  is  a  community  or  even  a 
county  problem,  in  some  cases  poisoning  being  required  by  local 
ruling.  Tons  of  paris  green  have  been  used  in  a  single  county 
in  one  year  during  a  serious  outbreak  and  the. result  has  well  re- 
paid the  expense  and  labor.  A  substitute  which  has  been  used 
considerably  is  the  Criddle  mixture,  prepared  by  poisoning  about 
100  pounds  of  fresh  horse  manure  with  one  pound  paris  green 
and  using  it  in  the  same  manner  as  the  bran  mash.  The  poisoned 
bran  mash  is  now  regarded  as  the  most  effective  means  for  the 
control  of  all  grasshoppers  which  are  commonly  injurious. 

The  Army  Worm  * 

Almost  every  year  some  locality  reports  serious  injury  to 
crops  by  armies  of  caterpillars,  which  have  not  been  previously 
known  for  many  years.     This  being  the  case  the  farmers  are 

at  a  loss  for  means  to  combat 
them,  and  by  the  time  the  in- 
formation has  been  secured  the 
pests  have  completed  the  damage. 
The  Army  Worm  occurs  through- 
out the  United  States  east  of  the 
Rocky  Mountains  and  lives  in 
low,  rank  growths  of  grass,  which 
form  thenormal  breeding-grounds. 
When  from  an  abundance  of  such 
food,  or  through  failure  of  the 
parasitesto  prevent  their  increase, 

the    caterpillars    become    over- 
FiG.  92. — Army-worm  moth  (Cirphus     i         i      .    ,r  ,i 

umpu«cto),  pupa,  and  eggs  in  natural  abundant,  they  assume  the  army 

position  in  a  grass-leaf.     Natural  habit  and  march  en  masse,  con- 
size.    (After  Comstock.)  suming  all  in  their  path. 
The  next  year  their  natural  enemies  will  usually  have  them 
under  control  again  and  there  will  be  but  little  damage,  and  then 
they  will  not  be  observed  as  injurious  for  a  series  of  years,  though 
the  moths  are  always  fairly  common. 

*  Cirphus  unipuncta  Haworth.    Family  Noduidoe. 


Fig.  93. — Army-worms  at  work  on  corn-plant.     (After  Slingerland.) 

Ill 


112       INSECT  PESTS  OF  FARM.  GARDEN  AND  ORCHARD 


Life  History. — In  the  North  the  moths  appear  early  in  June 
and  the  females  lay  the  small  yellowish  eggs  in  rows  of  from 
ten  to  fifty  in  the  unfolded  bases  of  the  grass  leaves,  covering 
them  with  a  thin  layer  of  glue.  Over  seven  hundred  may  be 
deposited  by  one  female,  so  that  when  the  young  caterpillars 
hatch,  in  about  ten  days,  the  progeny  of  a  few  moths  might 
form  a  quite  destructive  army.  The  worms  usually  feed  entirely 
at  night,  and  thus  whole  fields  will  sometimes  be  ruined  before 
they  are  discovered,  though  a  few  generally  feed  by  day,  as 
they  all  do  in  cloudy  weather.  The  leaves  and  stalks  of  grains 
and  grasses  form  their  favorite  food,  the  heads  usually  being 
cut  off,  but  various  garden  crops  are  often  seriously  injured  if 
they  happen  in  their  path.  Though  usually  untouched,  even 
clover  is  not  exempt.  In  from  three  to  four  weeks  the 
worms  have  become  full  grown  and  are  then  about  1^  to  2  inches 
long,  of  a  dark  gray  or  dingy  black  color,  with  three  nar- 
row, yellowish  stripes  above,  and  a  slightly  broader  and 
darker  one  on  each  side,  quite  resembling  cutworms,  to 
which  they  are  nearly  related.  They  now  enter  the  earth  and 
transform  to  pupae,  from  which  the  adult  moths  emerge  in  about 

two  weeks.  These  lay  eggs 
for  another  brood  of  worms 
which  appear  in  September, 
but  are  very  rarely  injuri- 
ous. The  moths  which  de- 
velop from  this  last  brood 
either  hibernate  over  winter 
or  deposit  eggs,  the  larvae 
from  which  become  partially 
grown  before  cold  weather 
and  then  hibernate.  In 
either  case  the  young  larvae 
feed  in  the  spring,  not  usu- 
ally doing  much  damage, 
pupate  in  May,  and  the 
moths  of  the  first  genera- 
tion appear  in  June  as 
already  described.  Thus  in 
the  North  there  are  three 


Fig.  94. — An  army 
w  o  r  m — a  bout 
one-third  en- 
larged. (After 
Chittenden,  U.  S. 
Dept.  Agr.) 


Fig.  95. — a,  head 
of  fall  army 
worm;  h,  head  of 
army  worm  — 
enlarged.  (After 
Chittenden,  U.  S. 
Dept.  Agr.) 


INSECTS    AFFECTING    GRAINS,    GRASSES,  ETC. 


113 


broods  a  year,  the  young  larvae  usually  hibernating,  while  in  the 
South  there  may  be  as  many  as  six  generations,  and  the 
moths  usuall}'^  hibernate  over  winter  and  lay  their  eggs  in  the 
spring. 

The  moths  very  often  fly  into  lights  and  are  among  the  com- 
monest of  our  plain  "  millers."  The  front  wings  are  a  clay  or 
fawn  color,  specked  with  black  scales,  marked  with  a  darker 
shade  or  stripe  at  the  tips,  and  with  a  distinct  spot  at  the  centre, 
which  gives  the  specific  name  unipimcta.  The  hind-wings  are 
somewhat  hghter  with  blackish  veins  and  darker  margins. 

Enemies. — Were  it  not  for  other  insects  which  pray  upon  the 
army- worm,  the  army  habit  would  doubtless  be  more  often 
assumed  and  we  should  have  to  deal  with  them  more  frequently. 
Ordinarily,  however,  the  parasitic  and  predaceous  insects  hold 


Fig.  96. — The  farmer's  friend,  the  red-tailed  tachina-fly  (Winthemia  4-pustu- 
lata):  a,  natural  size;  b,  much  enlarged;  c,  army  worm,  on  which  fly 
has  laid  eggs,  natural  size;  d,  same,  much  enlarged.     (After  Slingerland.) 

them  in  check  very  efficiently  and  when  an  outbreak  does  occur, 
the  later  broods  of  the  same  season  are  often  entirely  destroyed  by 
their  insect  enemies.  Large  numbers  are  always  destroyed  by  the 
predaceous  ground-beetles  and  their  larvse  (p.  13),  but  their 
most  deadly  enemies  are  the  tachina-fiies  (p.  104)  These  lay 
from  a  dozen  to  fifty  eggs  on  a  caterpillar,  and  the  maggots 
from  them  enter  the  body  and  absorb  the  juices  and  tissues  of 
the  host,  thus  soon  killing  it.     "When  feeding  at  night  the  worms 


114  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

are  ordinarily  free  from  these  parasites,  but  when  the  marching 
habit  is  assumed  the  flies  swarm  around  them  on  cloudy  days 
and  before  the  next  year  they  again  have  the  remnants  of  the 
voracious  army  under  subjection.  Therefore,  worms  with  the 
tachina-fly  eggs  on  them  (Fig.  95)  should  never  be  destroyed 
where  avoidable. 

Control. — When  detected,  all  efforts  should  be  centred  on 
keeping  the  worms  out  of  crops  not  yet  attacked  and  confining 
their  injury  to  as  small  an  area  as  possible.  As  a  barrier  to  their 
progress,  there  is  nothing  better  than  a  dust  furrow  made  as 
already  described  for  chinch-bugs  (p.  92),  two  or  three  of  which 
may  be  found  necessary  in  cool  weather  or  where  a  fine  dust  can- 
not be  maintained 

Deep  fall  plowing  and  thorough  harrowing  will  be  effective 
against  the  hibernating  larvae,  as  will  the  burning  of  all  grass 
along  ditches,  fences,  and  spots  where  the  larvae  normally  live. 

By  thorough  spraying,  or  perhaps  better  by  dusting,  a  strip 
of  the  crop  with  Paris  green  or  some  arsenical,  and  hberally 
distributing  poisoned  bran  mash  (see  p.  57),  large  numbers 
may  be  destroyed.  Where  they  are  massed  in  furrows  they 
may  be  destroyed  by  spraying  them  with  pure  kerosene  or  crude 
petroleum. 

As  in  fighting  chinch-bugs  the  army  worm  must  be  given 
immediate  and  conclusive  combat  if  the  loss  of  crops  is  to  be 
prevented,  for  they  move  rapidly  and  destroy  all  in  their  path. 

The  Fall  Army  Worm  or  Grass  Worm  * 

Though  somewhat  the  same  in  its  habits  as  the  true  army- 
worm,  the  Fall  Army  Worm  is  so  called  because  it  appears  later 
in  the  season,  the  former  species  being  rarely  injurious  after 
August  1st.  It  is  also  more  omnivorous,  for  while  the  army- 
worm  prefers  grasses,  and  grains,  the  fall  army-worm  feeds 
upon  a  large  variety  of  crops,  including  sugar-beets,  cow-peas, 
millet,  sweet  potatoes,  and  many  other  forage  and  truck  crops. 
In  Nebraska  and  the  Central  West  it  is  a  serious  pest  of  alfalfa 
and  is  called  the  Alfalfa  Worm.     It  is  also  sometimes  very  de- 

*  Laphygma  frugiperda  S.  and  A.     Family  Noduidce.    See  Farmers'  Bulletin 
752,  U.  S.  Dept.  of  Agriculture.     Walton  and  Luginbill. 


INSECTS    AFFECTING    GRAINS,    GRASSES,  ETC.        115 


structive  to  lawns,  as  was  the  case  in  Chicago  in  1899.  The  fall 
arm3'--woriii  is  more  of  a  native  of  the  Southern  States,  but 
occurs  from  Canada  to  the  Gulf  and  west  to  the  Rockies. 

At  first  glance  the  caterpillars  have  much  the  same  general 
appearance  as  the  army  worm,  but  closer  examination  reveals 
marked  differences.  Along  each  side  of  the  body  is  a  longitudinal 
pitch-colored  stripe,  and  along  the  middle  is  a  yellowish-gray 
stripe  about  twice  as  wide,  which  includes  four  black  dots  on 
each  segment.  The  caterpillars  assume  the  habit  of  working 
in  armies,  but  usually  do  not  feed  in  such  large  numbers  as  the 
true  army  worms  and  thus  are  more  difficult  to  combat. 

Life  History. — The  winter  is  passed  in  the  pupal  state,  the 
pupae  being  about  one-half 
inch  long  and  being  found 
in  cells  one-quarter  to  one- 
half  an  inch  below  the  sur- 
face. The  moths  emerge  in 
the  spring  and  the  females 
lay  their  eggs  on  grass  in 
clusters  of  fifty  or  more,  each 
mass  being  covered  with  the 
mouse-colored  hairs  from  the 
body  of  the  female.  The 
eggs  hatch  in  about  ten 
days  and  the  caterpillars  are 
found  during  May  and  June. 
The  complete  life  histor}^  of 
the  insect  has  not  been  care- 
fully followed,  but  it  seems 
probable  that  there  are-  but 
two  complete  generations  in 
the    North,   three  generations   in   the   latitude 


Fig.  97. — The  fall  army-worm:  a,  moth, 
plain  gray  form;  6,  fore  wing  of  Pro- 
denia-like  form;  c,  larva  extended;  d, 
abdominal  segment  of  larva,  side  view; 
e,  pupa;  d,  twice  natural  size,  others 
enlarged  one-fourth.  (After  Chittenden, 
U.  S.  Dept.  Agr.) 


of    central    and 

southern  Illinois  and  the  District  of  Columbia,  and  four  in  the 
extreme  South.  In  any  event,  the  destructive  brood  of  cater- 
pillars appears  in  August  and  early  September. 

The  parent  moth  is  of  a  "general  yellowish,  ash-gray  color, 
with  the  second  pair  of  wings  almost  transparent,  but  with  a 
purplish  reflection.  In  extent  of  wings  it  measures  about  Ij 
inches,  and  when  closed  the  length  of  the  insect  is  about  three- 


1 16       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

quarters  of  an  inch.  The  front  wings  are  mottled  or  marbled, 
especially  near  the  central  area,  and  usually  there  is  visible 
a  fine  white  line  a  short  distance  from  the  edge  and  parallel 
to  it.  The  hind-wings  have  a  fringe  of  darker  hair  as  well 
as  veins  that  contrast  somewhat  with  the  lighter  portion " 
(Fig.  97). 

Control. — Deep  fall  plowing  and  thorough  harrowing  will 
break  up  the  pupal  cells  and  thus  largely  prevent  the  develop- 
ment of  the  spring  brood  of  moths.  In  perennial  crops  like 
alfalfa  thorough  disking  may  be  used  and  on  lawns  deep  raking 
with  a  long-toothed  steel  rake  will  kill  many  of  the  pupae.  In 
fields  of  young  grain  and  on  lawns  many  of  the  caterpillars  may 
be  killed  by  a  heavy  roller.  When  not  present  in  too  large 
numbers,  the  worms  may  be  destroyed  by  spraying  the  food 
plants  with  Paris  green,  arsenate  of  lead  or  other  arsenicals, 
or  by  the  use  of  poisoned  bran  mash.  When  present  in  large 
numbers  and  the  army  habit  is  assumed  they  should  be  com- 
bated the  same  as  the  army-worm. 


CHAPTER  VIII 

INSECTS  INJURIOUS  TO  SMALL  GRAINS  * 

The  Hessian  Fly  f 

The  Hessian  fly  is  much  the  most  destructive  of  the  insects 
attacking  wheat,  to  which  its  injury  is  practically  confined; 
for  though  it  occasionally  injures  barley  and  rye,  it  has  never 


Fig.  98. — ^The  Hessian  fly  (Mayetiola  destructor):  a,  female  fly;  b,  flaxseed 
stage  or  pupa;  c,  larva;  d,  head  and  breast-bone  of  same;  e,  pupa; 
/,  puparium;  g,  infested  wheat-stem  showing  emergence  of  pupae  and 
adults.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

been  reared  on  other  grains  or  grasses.     Its  name  was  received 
from    the    fact  that    it   was  first  noticed   on   Long  Island   in 

*  Mayetiola  destructor  Say.     Family  Ceddomyiidoe. 

t  See  "The  Principal  Insect  Enemies  of  Growing  Wheat,"  C.  L.  Marlatt, 
Farmers'  Bulletin  No.  132,  U.  S.  Department  of  Agriculture. 


117 


118        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


1779,  near  where  the  Hessian  troops  had  landed  three  years  before. 
It  now  occurs  over  the  main  wheat-growing  area  of  the  eastern 
United  States  between  parallels  35°  and  45°  westward  to  the  100th 
meridian,  on  the  Pacific  coast,  in  Canada,  and  in  many  other  parts 
of  the  world  where  wheat  is  grown.  Not  infrequently  it  destroys 
25  to  50  per  cent  of  the  whole  crop  in  some  localities,  and  it  has 
been  estimated  that  10  per  cent  of  the  crop  of  the  whole  country 
is  lost  from  its  ravages. 

Life  History. — The  adult  flies  are  little  dark-colored  gnats  about 
one-tenth  inch  long,  so  small  as  to  escape  common  observation. 
Each  female  lays  100  to  150  minute  reddish  eggs,  one-fifteenth 

inch  long,  placing 
them  in  irregular 
rows  of  from  three 
to  five  or  more, 
usually  upon  the 
upper  surface  of  the 
leaves.  In  a  few 
days  these  hatch 
into  small,  reddish 
maggots,  which 
soon  turn  white,  are 
cylindrical,  about 
twice  as  long  as 
broad  and  have  no 
true  head  or  legs. 
The  fall  brood  mag- 
gots  burrow  be- 
neath the  sheath  of 
the  leaf  and  its  base, 
causing  a  sHght  en- 
largement at  the  point  of  attack,  but  in  the  spring  they  usually 
stop  at  one  of  the  lower  joints,  in  both  instances  becoming  fixed 
in  the  plant,  absorbing  its  sap  and  destroying  the  tissues.  The 
first  indications  of  the  work  of  the  maggots  on  winter  wheat  in 
the  fall  are  the  tendency  of  the  plants  to  stool  out,  the  dark 
color  of  the  leaves  and  the  absence  of  the  central  stems.  Later 
many  of  the  plants  yellow  and  die.  The  spring  maggots  attack 
the  laterals,  or  tillers,  which  have  escaped  the  previous  brood, 


Fig.  99. — The  Hessian  fly,radult  male — greatly  en- 
larged.    (After  Marlatt,  U.  S.Dept.  Agr.) 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


119 


so  weakening  them  that  the  steins  break  and  fall  before  ripening 

and  cannot  be  readily  harvested. 

About  four  weeks  after  hatching  the  maggots  are  full  grown, 

and  are  greenish-white  and  about  three-sixteenths  inch  long.     The 

skin  then  turns  brown, 
shrivels  slightly,  and 
inside  it  is  formed  the 
pupa.  This  outside 
case,  composed  of  the 
cast  larval  skin,  is 
known  as  the  "pupa- 
rium,"  and  this  stage 
is  commonly  called  the 
"flaxseed"  from  the 
resemblance  to  that 
seed.  In  this  stage 
most  of  the  fall  brood 
passes  the  winter,  the 
flies  emerging  in  April 
or  May,  while  the 
summer  brood  remains 
in  the  "flaxseed"  stage 
in  the  stubble  during 
the  late  summer  and 
emerges  when  the  first 
wheat  is  planted  in  the 
fall,  emerging  later  far- 
ther south. 

Several  species  of 
small  chalcis  flies  (page 
19)  parasitize  the  larvae 
and  pup£e  and  were  it 
not  for  their  assistance 
raise  wheat.  As  yet  no  prac- 
as   been  devised. 


Fig.  100. — "Flax-seeds"  or  puparia  of  the  Hes- 
sian fly  on  young  wheat  —  enlarged.  (After 
Pettit.) 


it  would  doubtless  be  difficult  to 
tical  method  of  increasing  their  abundance 
though  colonies  have  been  carried  to  regions  where  they  were  scarce 
Control. — The  principal  means  of  avoiding  injury  by  the  Hes- 
sian fly  in  the  winter  wheat  regions  is  late  planting  in  the  fall 
Inasmuch  as  the  flies  appear  within  ^about  a  week  and  then  dis- 


120       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCAHRD 


appear,  if  planting  be  delayed  until  after  that  time,  but  little  of  the 
wheat  will  be  injured.  Dry  weather  in  late  summer  and  early 
fall  will  delay  the  appearance  of  the  flies,  even  with  normal  tem- 
perature conditions,  and  the  further  south,  the  later  they  appear. 
From  experiments  being  conducted  by  the  U.  S.  Bureau  of  Ento- 
mology, Professor  F.  M.  Webster  states  that  the  following  dates  will 
probably  be  found  safe  for  sowing  wheat  in  average  seasons:  in 
northern  Michigan  soon  after  the  1st  of  September;  in  southern 
Michigan  and  northern  Ohio,  about  September  20th;  in  southern 
Ohio  after  the  first  week  in  October;  in  Kentucky  and  Tennessee, 
October  10th  to  20th;  in  Georgia  and  South  Carolina,  October 
25th  to  November  15th.  The  exact  time  will  also  depend  upon 
altitude  as  well  as  latitude. 

A  rotation  of  the  wheat  crop  compels  the  flies  when  they  emerge 
from  the  stubble  to  travel  in  search  of  the  young  wheat  plants. 
Should  storms  or  heavy  winds  occur,  the  frail  little  flies  will  be  de- 
stroyed in  large  numbers,  whereas  if  they  found  wheat  immedi- 
ately available  the  mortality  would  be  small. 


If 


Fig.  101. — Hessian  fly:  a,  egg,  greatly  enlarged;  b,  section  of  wheat-leaf 
showing  eggs  as  usually  deposited  —  less  enlarged;  c,  larva;  d,  pupa 
taken  from  puparium  or  "flaxseed"  —  e,  c,  d,  e,  much  enlarged.  (After 
Webster  and  Marlatt,  U.  S.  Dept.  Agr.) 

Inasmuch  as  most  of  the  spring  brood  remain  in  the  stubble 
in  the  flaxseed  stage  after  harvest,  if  the  fields  be  then  burned 
over,  large  numbers  will  be  destroyed.  This  may  be  done  by  cut- 
ting the  grain  rather  high  at  harvest,  and  then  mowing  the  weeds 
and  grass  and  allowing  them  to  dry  a  few  days  before  burning. 


INSECTS  INJURIOUS  TO  SMALL  GRAINS  121 

Unfortunately  this  practice  is  often  impossible,  owing  to  the  prac- 
tice of  seeding  wheat  land  to  grass  and  clover. 

As  early  volunteer  plants  always  become  badly  infested  and  the 
pupse  wintering  on  them  give  rise  to  a  spring  brood  which  attacks 
the  main  crop,  all  volunteer  plants  should  be  destroyed  by  plowing 
or  disking  before  the  larvse  have  matured.  This  principle  has  some- 
times been  utilized  in  the  form  of  a  trap  crop,  strips  of  wheat  being 
sown  early  so  as  to  attract  the  flies  and  then  being  plowed  under 
after  the  bulk  of  the  eggs  had  been  laid  upon  them,  thus  protecting 
the  main  crop,  planted  later. 

The  enrichment  of  the  soil,  the  preparation  of  a  good  seed  bed, 
and  the  use  of  good  seed,  so  as  to  secure  a  vigorous  growing  crop, 
are  all  of  the  greatest  importance  in  overcoming  injury  by  the 
Hessian  fly.  After  the  crop  is  once  attacked,  no  truly  remedial 
measures  are  known  except  to  apply  liberally  some  quick-acting 
fertilizer  which  will  cause  the  plants  to  tiller  freely  and  give  them 
sufficient  vigor  to  withstand  the  winter  and  thus  increase  the 
healthy  stems  the  next  spring. 

Of  late  years  the  practice  in  some  of  the  principal  wheat  growing 
states,  notably  in  Kansas,  has  been  to  plow  the  wheat  stubble 
under  deeply,  destroy  all  volunteer  plants  and  to  roll  or  pack 
in  some  manner  the  soil  in  the  plowed  fields  so  that  the  adult 
flies  will  be  unable  to  make  tlieir  escape  from  the  buried  pupse. 
This  is  recommended  as  the  best  means  of  control  but  may  well 
be  practiced  along  with  sowing  after  the  "fly-free"  date  as  deter- 
mined for  the  region  in  question. 

Some  work  with  immune  or  partially  immune  varieties  is  in 
progress  but  no  results  of  a  definite  nature  have  been  announced. 

Keeping  the  soil  in  first  class  condition  and  practicing  rotation 
and  other  matters  of  the  best  farming  practice  will  help  to  keep  the 
damage  from  the  fly  from  being  so  serious  during  any  season  as 
it  might  otherwise  have  been. 

The  Wheat  Joint-worm  * 

For  the  last  sixty  years  the  joint- worm  has  been  known  as 
a  serious  pest  of  wheat  tliroughout  the  wheat-growing  region 
east    of   the    Mississippi    River,    the    damage    varying    from    a 

*  Harmolita  tritici  Fitch.     Family  Chalcididce. 

See  W.  J.  Phillips,  U.  S.  Dept.  Agr.  Bulletin  808,  and  Farmers'  Bul- 
letin 1006. , 


122       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


slight  injury  which  is  hardly  noticeable,  and  which  may  escape 
observation  for  several  years,  to  an  almost  total  infestation  of 
the  crop. 

The  adults  appear  inApril,  May,  or  early  June,  according  to  the 
latitude,  and  are  small  black,  four-winged  flies  about  one-eighth 
inch  long,  with  the  joints  of  the  legs  and  feet  yellow.  They  look 
something  like  small,  winged  black  ants  (Fig.  102)  and  curiously 
enough  belong  to  a  family  whose  members  are  almost  all  parasitic 
on  other  insects,  so  that  before  they  had  been  thoroughly  studied 
they  were  thought  to  be  parasites  of  the  Hessian  fly.  The  females 
lay  their  eggs  in  the  stems,  generally  selecting  the  uppermost 

joints  that  have  ap- 
peared at  that  time. 
"  The  young  worms 
develop  rapidly,  each 
in  a  little  cavity  within 
the  straw.  Often 
knots,  swellings,  and 
twistings  occur  in  the 
straw  at  the  point  of 
infestation;  again 
there  is  little  sign  of 
the    insect's    presence 

Fig.  102. — a,  wheat-straw  affected  by  joint-worm;  except  a  slight  discol- 
b,  adult  as  seen  from  above.     (After  Riley.)         ^^^^-^^  ^^  ^  ^^^j^  ^^_ 

viation  of  the  fibres  and  grooves  of  the  straw  from  their  natural 
course.  When  the  infested  section  is  split  with  a  knife  it  is  found 
to  be  brittle  and  woody  in  character,  and  contains  from  3  or  4 
to  20  or  more  yellowish  larva,  about  one-eighth  inch  long  when 
full-grown.  These  larva  remain  in  the  straw  until  the  following 
spring,  when  they  issue  as  adults  and  commence  again  the  life 
cycle  in  the  new  crop.  The  damage  is  done  by  the  worms  cut- 
ting off  the  sap  supply  from  the  head,  causing  it  to  become 
shortened,  containing  comparatively  few  kernels,  and  such 
kernels  as  develop  are  apt  to  be  small  and  shriveled  from  lack 
of  nourishment.  Also  because  of  the  brittleness  of  the  straw  high 
winds  are  apt  to  break  much  of  it  down." — Gossard. 

The  presence  of  the  pest  is  always  indicated  at  threshing  by 
short,  hard  bits  of  straw,  containing  the  larvae,  which  are  carried 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


123 


out  \vith  the  grain  instead  of  going  over  in  the  straw.  It  has 
Usually  been  considered  necessary  to  separate  and  burn  these, 
but  Professor  F.  M.  Webster  finds  that  the  larvie  in  them  are 
probably   killed   in   thresliing,   as   he   has   been   unable   to   rear 


Fig.  103. — Swellings  made  by  wheat  joint-worms  in  straw — enlarged.      (After 

Pettit.) 

adults  of  either  the  joint-worm  or  its  parasites  from  such  bits  of 
straw. 

Control. — ^A  rotation  of  the  wheat  crop  is  of  prime  impor- 
tance in  the  control  of  this  pest,  and  where  wheat  is  not  planted 
on  the  same  land 
and  is  sown  as  far 
from  that  of  the 
previous  year  as 
possible  there  will  be 
but  httle  damage. 
It  is  obvious  that 
the  stubble  should 
be  plowed  under 
where  possible,  or 
burned  during  the 
late  fall  or  winter. 
Cut  infested  grain 
as  low  as  possible 
so  as  to  remove  the 
larvae  in  the  straw. 


Fig  lU-i^ — \v  neat  straw-worn:  adult  of  fall  genera- 
tion, much  enlarged.  (After  Howard,  U.  S. 
Dept.  Agr.) 


Where  the  stubble  cannot  be  biu-ned,  break 
it  down  by  harrowing  in  the  spring  and  then  collect  with  a  hay- 


124         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


rake  and  burn.  Prepare  the  seed  bed  thoroughly  and  fertiHze  well, 
when  injury  is  expected,  so  as  to  ensure  a  strong  growth  and 
early  ripening.  Green  manure  containing  infested  straw  should 
not  be  scattered  on  land  to  be  used  for  wheat,  and  all  infested 
straw  which  has  not  been  used  up  by  April  should  be  burned. 

The  Wheat  Straw-worm  * 

"  The  Wheat  Straw-worm,"  says  Professor  F.  M.  Webster,  "  sus- 
tains the  same  relation  to  winter-wheat  culture  west  of  the  Miss- 
issippi River  that  the  joint-worm  does  to  the  cultivation  of  this 
cereal  east  of  this  river.  Both,  when  excessively  abundant, 
occasion  losses  from  siight  to  total.  A  wheat  stem  attacked 
by  the  joint- worm  may  produce  grain  of  a  more  or  less  inferior 
quality  and  less  of  it;  but  the  spring  attack  of  the  wheat  straw- 
worm  is  fatal  to  the  plant  affected,  as  no  grain  at  all  is  produced, 
and  while  the  second  generation  of  the  same  has  a  less  disastrous 
effect  in  the  field,  it  nevertheless  reduces  the  grade  and  weight 


Fig.  105. — ^Wheat  straw-worm  a,  ventral  view;  h,  side  view  of  larva;  c, 
antenna?;  d,  mandible;  e,  anal  segment,  ventral  view;  /,  adult  female; 
g,  fore- wing;    h,  hind-wing;    i,  aborted    wing.         (After  Riley.) 

of  the  grain."  Though  the  straw-worm  occurs  over  much  of 
the  same  territory  in  the  East  as  the  joint-worm,  it  is  rarely  so 
injurious. 

Life  History  and  Description.] — "  There  are  two  generations 

*  Harmolita  grandis  Riley.     Family  Chalcididcs. 
See  W.  J.  Phillips,  U.  S.  Dept.  Agr.  Bulletin  SOS. 

t  From  Circular  106,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  by  F.  M. 
Webster  and  Geo.  I.  Reeves. 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


125 


of  the  insect  annually,  the  adults  of  the  first  generation  differing 
considerably  in  appearance  from  those  of  the  second.  To  the 
farmer  they  will  all  look  like  minute  or  large,  shining  black  ants, 
with  or  without  wings,  their  legs  more  or  less  banded  with  yellow, 
and  having  red  eyes.  Individuals  of  the  first  generation  emerge 
in  April  from  the  outstanding  straws  and  stubble.  They  are 
very  small,  most  of  them  are  females,  and  many  are  wingless. 
The  females  deposit  their  eggs  in  the  young  wheat  plants,  the 
stems  of  which  at  this  time  extend  but  little  above  the  sur- 
face of  the  ground.  The  egg  is  placed  in  or  just  below  the 
embryonic  wheat  head  and  the  larva  or  worm  works  within 
the  stem,  usually  causing  a  slight  enlargement.  When  the 
worm  is  full  grown  it  will  be  found  in  the  crown  of  the  plant, 
having  eaten  out  and  totally  destroyed  the  embryonic  head, 
its  bod}'-  occupying  the  cavity  thus  formed. 

''  The  females  which  deposit  these  eggs,  being  small  and  fre- 
quently wingless,  are  in  no  way  fitted  for  traveling  long  dis- 
tances. The  larva  or  worm  is  of  a  very  light  straw  color,  indeed 
almost  white,  with  brown  jaws.  These  worms  develop  very 
rapidly  and,  as  they  feed 
on  the  most  nutritious  part 
of  the  plant,  they  become 
robust  and  larger  than 
those  found  in  the  mature 
straw  in  late  summer.  In 
May  the  larvae  become  full 
grown  and  pass  at  once 
through  a  short  pupal 
stage.  The  pupae  are  at 
first  the  same  color  as  the 
larvae,  but  later  change  to 
a  shining  jet  black, 
a  few  days  the  fully  devel- 
oped insects  gnaw  circular 
holes  through  the  walls  of 
the  stem  and  make  their 
way  out.  These  adults  are  much  larger  and  more  robust  than 
the  individuals  of  the  first  generation  and  arc  provided  with 
fully  developed,  serviceable  wings.     That  they  make  good  use  of 


In  Fig.  106. — Thewheatstraw-worm:  method 
of  oviposition  of  female  of  summer  form : 
a,  female  inserting  her  eggs;  h,  section 
of  wheat  stem,  showing  egg;  c,  and 
ovipositor,  d;  c,  egg,  greatly  magnified. 
(After  Riley  and  Webster,  U.  S.  Dept. 
Agr.) 


126         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


their  wings,  and  scatter  themselves  about  over  fields  adjacent  to 
their  place  of  development,  is  shown  by  their  occuiTence  in  fields 
of  grasses  (in  the  stems  of  which  they  do  not  breed)  situated 
considerable  distances  from  wheat  fields.  In  ovipositing,  the 
females  of  this  generation  select  the  largest  and  most  vigorous- 
growing  stems  in  wliich  to  place  their  eggs. 

"  The  adults  of  the  second  generation  deposit  their  eggs 
from  early  May,  in  Texas,  up  to  the  middle  of  June,  in  northern 
Indiana,  or  about  the  tune  the  wheat  is  heading.  Their  aim 
at  this  time  is  to  place  the  eggs  singly  in  the  growing  stem, 
just  above  the  youngest 
and  most  succulent  joints, 
which  are  not  so  covered 
by  the  enfolding  leaf 
sheaths  as  to  be  inaccessi- 
ble to  them.  Thus  it  is 
that  the  stage  of  advance- 
ment in  the  growth  of  the 
wheat  stem  at  the  time  of 
oviposition  of  the  summer 
generation  of  females 
determines  whether  the 
larvae  will  be  well  upward 
in  the  straw,  and  there- 
fore removed  after  har- 
vest, or  lower  down  and 
consequent^  left  in  the 
field  in  the  stubble. 

"The  method  of  ovi- 
position and  the  point 
where  the  egg  is  usually 
formed  is  shown  in  Fig. 
103.  The  larva  forms  no 
gall,  nor  does  it  harden 
the  stem  within  which  it 
develops.  There  is  nor- 
mally but  one  larva  in  each  joint;  but  if  several  eggs  have  been 
placed  between  joints  and  produce  larvae  there  will  be  one  in  the 
centre  of  the  stem  just  above  the  joint  and  others  in  the  walls  just 


Fig.  107. — Wheat  straw-worm,  showing 
point  where  female  of  the  spring  form 
deposits  the  egg  in  young  wheat  in  early 
spring.  Enlarged  showing  position  of  egg 
at  right.  (After  Webster,  U.  S.  Dept.  Agr.) 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


127 


under  the  internal  wall-covering  or  inner  epidermis.  These  larvae 
in  the  walls  of  the  straw  do  not,  as  a  rule,  kill  the  stem,  but 
their  effect  is  to  curtail  the  yield  by  reducing  the  weight.  The 
larvse  develop  rapidly  and  reach  their  full  growth  before  the 
straw  has  hardened.  By  Octoljer,  in  the  Middle  West,  though 
earlier  in  the  South,  they  pass  into  the  pupal  stage,  in  which,  as  a 
rule,  they  remain  until  early  spring,  whereupon  they  develop  to 
adults  and  gnaw  their  way  out."  In  the  Northwest,  where  both 
winter  and  spring  wheat  are  grown,  the  injury  is  particularly 
severe  to  spring  wheat,  as  the  adults 
of  the  second  generation  from  winter 
wheat  oviposit  upon  it  while  it  is 
still  young  and  ruin  it  in  much  the 
same  way  as  the  first  generation  does 
on  the  winter  wheat  in  spring.  Vol- 
unteer plants  which  carry  the  pest 
over  winter  have  the  same  effect  in 
increasing  the  injury  to  spring  wheat. 
Control.  — A  rotation  of  crops 
which  will  eliminate  the  growing  of 
wheat  two  years  in  succession  on  the 
same  land  is  by  all  means  the  most 
successful  and  practicable  means  of 
control.  The  adults  of  the  first  gene- 
ration are  very  small  and  largely 

mngless;^they  are  unable  to  migrate  Fig.  108. — ^The  wheat  saw-fly  borer 
far,  so  that  rotation  is  exceedingly 
efficacious,  though  it  should  be 
planned  so  that  wheat  is  not  planted 
next  to  stubble  land,  for  the  edge 
will  become  infested  by  the  first  gene- 
ration, and  the  second  generation 
will  then  become  distributed  throughout  the  field.  The  burn- 
ing of  stubble  and  outstanding  straw  will  be  advantageous 
wherever  practicable.  Clean  fallowing  in  early  summer  and  the 
abandonment  of  spring-wheat  culture  will  reduce  injury  in  the 
Northwest. 


(Cephus  pygmoEUs  Linn)  :j  a,  out- 
line of  larva,  natural  size;  b, 
larva,  enlarged;  c,  larva  in  wheat- 
stalk,  natural  size;  d,  frass;  e, 
adult  female;  /,  Pachyoneruscal- 
citrator,  female,  a  parasite — en- 
larged. (After  Curits,  from 
"Insect  Life.") 


128 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Saw-Flies  Attacking  Wheat  * 

Several  members  of  the  Hymenopterous  family  commonly 
called  saw-flies,  are  occasionally  found  feeding  on  wheat  but 
scarcely  deserve  to  be  ranked  as  pests.  One  of  these  is  the  Wheat 
Saw-fly  Borer,  t  and  another  is  called  the  Western  Grass-stem 
Saw-fly.| 

The  former  is  an  importation  from  Europe  while  the  latter  is  a 
native  insect  and  is  more  common  in  the  Northwest  than  in  the 
Eastern  States. 

Both  species  bore  in  the  stems  of  wheat  and  some  other  grass 


Fig.' 109. — The  western  grass-stem  saw-fly  (Cephus  occidentalis) :  a,  larva; 
b,  female  saw-fly;  c,  grass-stem  showing  work;  c,  enlarged,  a,  b,  more 
enlarged.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

plants.  Eggs  are  laid  in  the  stem  and  a  single  larvae  develops 
and  feeds  within  the  stem  until  full  grown  when  it  pupates  with- 
in the  part  of  the  stem  which  is  underground  and  there  spends 
the  winter.     The  adults  appear  about  May. 

Remedies. — Rotation  of  crops,  burning  of  stubble  and  plowing 
the  stubble  under  deeply  are  the  remedies  suggested,  should  any 
be  needed  on  account  of  the  serious  increase  of  the  pests. 

*  Family  Tenthredinidw. 
t  Cephus  pygmceus  Linn. 
X  Cephus  occidentalis,  Riley  and  Marlatt. 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


129 


Other  species  of  saw-flics  feed  on  the  leaves  and  even  on  the 
heads  of  wheat.     Tliey,  hke  the  stem-borers,  are  rarely  abundant 

enough  to  be  trouble- 
some. Among  these  are 
two  species  called  merely 
wheat  saw-flies  (Dolerus 
arvensis  Say  and  Dolerus 
collaris  Say).  These 
species  occur  throughout 
the  United  States  and 
southern  Canada,  east  of 
the  Rockies.  These  saw- 
flies  are  fairly  large,  com- 
pared with  the  ones  pre- 
FiG.  110. — A  wheat    saw-fly    (Dolerus  arvensis      .        ,       ,.  ,         ^, 

Say):  female— much  enlarged.     (After  RUey  VlOUSly  dlSCUSSed.        ihe 
and  Marlatt,  U.  S.  Dept.  Agr.)  adults    appear    as    dull 

black  or  bluish  four-winged   flies,  marked    inconspicuously  with 


Fig.  111. — The  grass  saw-fly  {Pachynematus  extensicornis  Norton):  a,  a,  eggs 
on  wheat-blade;  h,  young  larva?;  c,  full-grown  larva;  d,  cocoon  from 
which  adult  has  emerged;  e, /,  adult  insects — e,  male;/,  female,  a  and 
fe,  natural  size;  c-/,  enlarged.    (After  Riley  and  INIarlatt,  U.  S.  Dept.  Agr.) 


130         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

reddish  or  yellow.  The  larvae  are  grayish  above  and  lighter 
beneath  and  reach  a  length  of  about  a  half-inch.  They  appear 
like  any  common  small  caterpillar  but  on  examination  will  be 
found  to  have  eleven  pairs  of  legs  in  place  of  the  eight  pairs  found 
on  the  caterpillars. 

A  third  species,  more  common  than  any  of  the  others  is  the 
Grass  Saw-fiy,  (Pachynematus  extensicornis  Norton).  The  adults 
of  this  species  do  not  differ  markedly  from  the  others  but  the  larvae 
became  larger  and  are  green  or  yellowish-green  in  color  and  have 
only  ten  pairs  of  legs  in  place  of  the  eleven  pairs  found  in  the 
former  species. 

Adults  of  all  these  forms  appear  rather  early  in  the  spring  and 
larvae  feed  on  the  wheat,  then  in  mid-summer  go  into  the  ground 
and  remain  there  as  larvae  until  early  the  next  spring.  They 
may  possibly  be  destroyed  in  this  situation  by  deep  plowing, 
which  would  prevent  the  escape  of  the  adults.  So  far,  injury 
has  not  been  extensive  enough  to  call  for  treatment. 

Some  Wheat-maggots 

Very  similar  to  the  Hessian  fly  in  its  mode  of  injuring  the 
wheat-stalk  is  the  Wheat-stem  Maggot  (Meromyza  americana 
Fitch).  The  adult  flies  were  first  described  by  Dr.  Fitch  in  1856, 
though  the  work  of  the  maggots  had  probably  been  noticed  as 
early  as  1821  by  James  Worth  of  Bucks  County,  Pa.,  and  by  the 
Michigan  Farmer  in  Michigan  about  1845. 

Extending  from  Dakota  and  Manitoba  to  Texas,  the  range 
of  this  insect  practically  covers  all  the  eastern  United  States  and 
southern  Canada. 

Unlike  the  Hessian  fly  it  feeds  and  breeds  upon  wild  grasses  and 
is  thus  much  more  difficult  to  control.  Prof.  A.  J.  Cook  found 
the  larvae  in  both  barley  and  oats  in  Michigan,  Prof.  F.  M.  Webster 
reared  an  adult  from  blue  grass  (Poa  pratensis),  and  Dr.  Jas. 
Fletcher  records  it  as  breeding  in  Agropyrum,  Deschampsis,  Elymus, 
Poa,  and  Setaria  viridis  in  Canada. 

Life  History. —  Like  the  Hessian  fly  the  adult  flies  lay  their 
eggs  on  fall  wheat  in  September  and  October,  and  the  young 
maggots  when  hatched  work  their  way  down  into  the  stem,  either 
cutting  it  off  or  causing  it  to  discolor  or  die.  The  eggs  are  about 
one-fortieth  of  an  inch  long  and  of  a  glistening  white  color.    The 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


131 


larvae  are  a  light  greenish  color,  about  one-fourth  of  an  inch  long 
tapering  toward  the  terminal  end  while  subcylindrical  posteriorly, 
being  quite  elongate.  The  pupa?  are  the  same  color  as  the  larvae, 
but  more  rounded,  being  only  one-sixth  of  an  inch  long,  and  reveal 
the  legs  and  wing-cases  of  the  imago  forming  within  them.  The 
external  case  of  the  pupa,  called  the  puparium,  is  merely  the 
shrunken  and  hardened  cast  skin  of  the  last  larval  stage, 
within  which  the  insect  transforms  to  the  pupa.  The  fly  is 
about  one-fifth  of  an  inch  long.  It  is  of  a  yellowish-white 
color  with  a  black 
spot  on  the  top  of  the 
head,  three  broad 
black  stripes  on  the 
thorax,  and  three  on 
the  abdomen,  which 
are  often  interrupted 
at  the  sutures,  so 
that  they  form  dis- 
tinct spots.  The 
eyes  are  a  bright 
green. 

The  winter  is  pass- 
ed by  the  larvae  in  the 
young  plants  and  in 
spring  they  trans- 
form to  pupae  and 
adult  flies.  These  in 
turn  deposit  eggs  in 
such  a  position  that 
the  maggots  issuing  from  them  ma}'  readily  feed  upon  the  succulent 
portions  of  the  growing  stalk.  Numerous  larvae  thus  sapping  the 
life  of  the  plant  soon  kill  it  outright  or  cause  the  top  and  head  to 
wither  and  die.  The  adults  of  this  brood  emerge  in  July  and  lay 
eggs  on  volunteer  wheat  and  grasses,  the  maggots  working  in  the 
same  manner  as  in  the  fall  and  coming  to  maturity  so  that 
another  brood  of  flies  lays  eggs  for  the  fall  brood  on  the  newly 
planted  wheat. 

Owing  to  the  fact  that  this  insect  breeds  also  in  grasses  dur- 
ing late  summer  it  is  much  more  difficult  to  combat  than  were  it 
confined  to  wheat  as  its  food-plant,  as  is  the  Hessian  fly. 


Fig.  112. — Wheat  bulb-worm  (Meromyza  atneri- 
cana):  a,  mature  fly;  b,  larva;  c,  puparium; 
(/,  infested  wheat-stem — all  enlarged  except  d. 
(After  Marlatt,  U.  S.  Dept.  Agr.) 


132        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


■ai|jjp9^^?^#!ir 


Remedies. — "If  the  grain  is  stacked  or  threshed  and  the 
straw  stacked  or  burned,"  says  Professor  Webster/' it  is  clear  that 
the  number  escaping  would  be  greatly  reduced,"  for,  as  the 
adults  emerge  soon  after  harvest,  they  would  escape  to  deposit 
their  eggs  were  the  straw  left  in  the  fields,  but  "it  is  not  likely 
that  those  in  the  centre  of  the  stacks  would  be  able  to  make 
their  way  out,  and  the  threshing-machine  would  destroy  many 
more.  How  much  could  be  accomplished  by  late  sowing  of  grain 
is  uncertain,  as  the  females  are  known  to  occur  abundantly  up  to 
October.  If  plots  of  grain  were  sowed  immediately  after  harvest 
in  the  vicinity  of  the  stacks,  many  of  the  females  could,  no  doubt, 
a  be  induced  to  deposit 

MMMMMP|PWP"!i^fi|^  ^h^^    €ggs  therein,  and 
^j^^^^^^^^\^^gll^^/0  these  could  be  destroyed 

by  plowing   under." 
b  Burning  of  the  stubble 

will  also  aid  in  keeping 
this  pest  under  control. 
There  are  several 
undetermined  species  of 
flies  belonging  to  the 
genus  Oscinis ,  which 
have  practically  the 
same  life  history  as  the 
wheat  stem-maggot  and 
injure  the  wheat  in  the 
same  manner.     They 

Fig.  113.— The  American  frit-fly  (Oscinis  variabilis  ^^^^  closely  resemble 
Loew) :  a,  larva  or  maggot;  b,  puparium;  c,  adult  the  common  house-fly 
fly.    (After  Carman.)  ^^    miniature,     being 

about  one-fourth  as  large.  They  will  not  need  consideration  by 
the  practical  farmer  other  than  in  applying  methods  of  control 
as  already  given.  One  species  of  this  genus,  determined  by  Pro- 
fessor H.  Garman  as  Oscinis  variabilis  Loew  and  christened  the 
American  Frit-fly,  has  been  found  common  in  Kentucky  and 
Canada,  but  in  the  larval  stage  is  so  nearly  identical  in  appear- 
ance and  habit  with  the  stem-maggot  that  it  can  with  difficulty 
be  distinguished  from  it. 

That  these  pests  do  not  do  more  injury  is  probably  due,  to  a 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


133 


considerable  extent,  to  the  fact  that  large  numbers  of  them  are 
destroj^ed  by  a  small  hymenopterous  parasite,  known  as  Ccelinus 
meromyzce  Forbes,  which  very  commonly  infests  the  larvae,  and 
by  other  parasites  and  predaceous  insects. 

Rarely  will  these  pests  do  serious  damage,  but  very  often 
it  is  sufficient  to  merit  consideration,  and  onlj'  a  knowledge  of 
their  life  history  can  give  a  key  to  their  successful  control. 

The  Wheat-midge  * 

History. — While  the  Hessian  fly  attacks  the  stalk  of  the 
wheat-plant,  another  species  of  the  same  family,  known  as  the 


Fig  114. — Wheat-midge  {Diplosis  tritici):  a,  female  fly;  h,  male  fly;  c,  larva 
from  below.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

Wheat-midge,  or  "Red  Weevil,"  often  does  very  serious  damage 

to  the  maturing  head.     It,  too,  is  a  foreigner,  having  first  been 

noticed  as  injurious  in  Suffolk,  England,  in  1795,  though  probable 

references  to  its  depredations  date  back  as  early  as  1741.     "In 

'  Ellis's  Modern  Husbandman  '  for  1745  the  attacks  of  the  vast 

numbers  of  black   flies   (the  ichneumon  parasites)   are  noticed 

in  the  following  quaint  terms:  'After  this  we  have  a  melancholy 

sight,  for,  as  soon  as  the  wheat  had  done  blooming,  vast  numbers 

of  black  flies  attacked  the  wheat-ears  and  bio  wed  a  little  j^ellow 

maggot  which  ate  up  some  of  the  kernels  in  other  parts  of  them, 

and  which  caused  multitudes  of  ears  to  miss  of  their  fulness,  acting 

*  Diplosis  tritici.    Family  Cecidomyiidac.       See  Bulletin  No.  5,  Vol.  I,  2d 
Ser.,  Ohio  Agr.  Exp.  Sta.,  F.  M.  Webster. 


134  INSECT  PESTS  .OF  FARM,  GARDEN  AND  ORCHARD 

in  some  measure  like  a  sort  of  locust,  till  rain  fell  and  washed  them 
off;  and  though  this  evil  has  happened  in  other  summers  to  the 
wheat  in  some  degree,  yet  if  the  good  providence  of  God  had  not 
hindered  it  they  might  have  ruined  all  the  crops  of  wheat  in  the 
nation.'  (Hind's  '  Essay  on  Insects  and  Diseases  Injurious  to 
Wheat  Crops,'  page  76)".  It  seems  probable  that  it  was  first 
introduced  into  America  near  Quebec,  where  it  "  appears  to  have 
occurred"  in  1819,  and  was  first  observed  in  the  United  States 
in  northwestern  Vermont  in  1820.  It  did  not  become  very 
destructive,  however,  until  1828,  from  which  time  until  1835 
it  kept  increasing  in  such  numbers  as  to  cause  the  abandonment 
of  the  wheat  crops  in  some  localities  throughout  northern  New 
England.  Serious  damage  was  reported  as  due  to  this  pest 
every  few  years  until  about  1860,  being  most  severe  in  1854,  in 
which  year  Dr.  Fitch  estimated  the  loss  in  New  York  alone  at 
$15,000,000,  and  in  1857,  and  1858.  Since  then  no  widespread 
injury  has  occurred,  though  local  outbreaks  are  frequent,  and 
it  has  spread  south  to  the  Gulf  States  and  westward  to  Iowa, 
Minnesota,  and  Arkansas. 

Life  History. — The  adult  flies  are  small,  two- winged  insects, 
about  an  eighth  of  an  inch  long,  of  a  yellow  or  orange  color. 
They  appear  about  the  middle  of  June  and  lay  the  eggs  "in  a 
small  cavity  at  the  summit  of,  and  formed  by  a  groove  in,  the 
outmost  chaff  covering  the  incipient  kernel."  They  hatch  in 
about  a  week,  according  to  Dr.  Fitch,  and  the  maggots  burrow 
into  the  forming  kernels.  The  maggots  are  of  a  reddish  color, 
and  when  an  ear  is  badly  infested  give  it  a  reddish  tinge,  on 
account  of  which  the  insect  is  often  called  the  "red  weevil." 

When  full  grown  the  larvae  enter  the  ground  and  usually 
form  cocoons,  in  which  they  pass  the  winter  in  the  pupal  stage, 
though  they  often  hibernate  without  such  protection.  Though 
doubtless  there  is  usually  but  one  brood  in  a  season,  observations 
by  Professor  F.  M.  Webster  and  others  seem  to  point  to  the  fact 
that  there  sometimes  are  two  broods,  as  adults  have  been  observed 
from  August  into  November. 

Besides  wheat,  the  wheat-midge  also  sometimes  injures 
rye,  barley,  and  oats. 

Remedies. — Plowing  infested  fields  in  the  fall  so  deeply  that 
the  midges  will  be  unable  to  reach  the  surface  upon  developing 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


135 


in  the  spring  is  by  far  the  best  means  of  controlling  this  pest, 
while  burning  the  stubble  previous  to  plowing,  and  a  rotation 
of  the  crop,  will  also  be  of  considerable  aid. 


The  English  Grain-louse  * 

The  most  common  plant-louse  affecting  wheat  and  other  small 
grains  is  a  large  green  species  which  is  always  to  be  found  on 
wheat  plants,  but  which  occasionally  increases  very  rapidly,  and 
clustering  on  the  ripening 
heads  sucks  the  juices  so 
as  seriously  to  injure  the 
quality  and  weight  of  the 
wheat. 

In  the  North  the  first 
individuals  are  found  on 
young  wheat  in  April, 
though  during  open  win- 
ters they  may  be  found 
on  the  plants,  and  in  the 
South  they  continue  to 
reproduce  during  most  of 
the  winter  in  open  sea- 
sons. The  aphids  feed 
upon  the  leaves  until  the 
grain  commences  to 
head,  when  they  assem- 
ble on  the  heads  among  the  ripening  kernels.  The  females  give 
birth  to  live  young,  bearing  from  40  to  50  each,  which  become 
full  grown  in  ten  days  to  two  weeks,  and  then  reproduce,  as  is  the 
usual  method  of  reproduction  with  plant-lice  (see  page  390),  so  that 
they  multiply  with  great  rapidity,  and  where  so  few  were  present 
as  to  be  hardly  noticeable,  in  a  few  weeks  they  will  be  swarming 
over  the  heads  in  myriads.  As  the  small  grains  ripen  they  migrate 
to  various  grasses  and  are  not  much  in  evidence  during  midsummer, 

*  Macrosiphum  granaria  Buckton.  Family  Aphididoe.  A  nearly  related 
species,  Macrosiphuin  cerealis  Kaltenbach,  has  very  similar  habits,  is  commonly 
associated  with  the  species,  and  has  not  been  distinguished  from  it  by  most 
writers.  It  may  be  recognized  by  lacking  the  blackish  markings  on  the 
abdominal  segments.  See  Pergande,  Bulletin  44,  Bureau  of  Entomology, 
U.  S.  Dept.  Agr. 


Fig.  115. — The  German  grain  aphis(Macro- 
siphum  cerealis  Kalt):  a,  winged  migrant 
b,  nymph  of  same;  c,  wingless  partheno- 
genetic  female;  d,  same  showing  exit  hole 
of  parasite — enlarged.  (After  Riley,  U. 
S.  Dept.  Agr.) 


136  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


but  later  migrate  to  volunteer  oats  and  wheat,  upon  which  they 
subsist  until  fall  wheat  is  available.  Owing  to  the  cool  weather 
of  fall  and  the  fact  that  but  few  individuals  survive  the  attacks 
of  their  parasites  during  the  summer,  they  rarely  become  abundant 
enough  to  do  any  damage  to  grains  in  the  fall.  So  far  as  known, 
they  hibernate  over  winter  among  the  leaves  of  the  growing  plants, 
enough  surviving  both  snow  and  cold  to 
infest  the  crop  the  next  spring.  Whether 
true  males  and  females  produce  eggs  on 
the  grain  is  unknown,  for  though  they  have 
beenreared  under  artificial  conditions, 
they  have  never  been  observed  in  the  field. 


Fig.  116. — Grain  aphids 
clustered  on  wheat  head, 
greatly  enlarged.  (After 
Weed.) 


Fig.  117. — ^Wheat-louse  parasite  {Aphidius 
avenaphis  Fitch),  and  parasitized  louse 
from  which  it  has  issued.  (Copied  from 
J.  B.  Smith.) 


Professor  F.  L.  Washburn   observed  at  least  fourteen  generations 
up  to  November  8,  1907,  in  southern  Minnesota. 

As  with  other  aphids,  both  winged  and  wingless  individuals 
occur  throughout  the  season.  The  wingless  individuals  are 
about  one-tenth  inch  long,  with  black  antennse  as  long  as,  or  longer 
than  the  body,  are  of  a  yellowish-green  color,  often  slightly 
pruinose,  and  long  black  nectaries  extend  from  either  side  of  the 
abdomen.  The  winged  individuals  are  about  the  same  length, 
"with  a  wing  expanse  of  about  three-eighths  inch,  with  antennae 


INSECTS  INJURIOUS  TO  SMALL  GRAINS  137 

a  third  longer  than  the  body,  and  are  of  the  same  general  colora- 
tion except  that  lobes  of  the  thorax  are  brown  or  blackish,  and 
the  abdomen  is  marked  with  four  or  five  transverse  blackish 
spots  in  front  of  the  nectaries. 

Like  the  other  aphids  affecting  small  grains,  this  species  is 
held  in  check  by  parasitic  insects,  aided  by  predaceous  insects  and 
fungous  diseases.  Injury  by  the  aphids  is  usually  due  to  the 
parasites  having  been  killed  off,  thus  giving  the  aphids  oppor- 
tunity to  multiply  unchecked.  Among  the  most  abundant  parasites 
are  species  of  the  genus  Aphidius  (iaraily  Braconidce) ,  one  of  which 
is  shown  in  Fig.  117,  greatly  enlarged.  Cold,  wet  weather  in 
spring  greatly  retards  the  development  of  these  parasites, 
so  that  the  aphids  are  always  more  numerous  in  such  sea- 
sons. It  has  also  been  observed  that  an  outbreak  is  often  pre- 
ceded by  several  dry  seasons,  which  may  be  due  to  the  fact  that 
such  dry  seasons  check  the  development  of  fungous  diseases  which 
kill  off  large  numbers  of  the  aphids  and  which  do  not  propagate 
in  hot  dr}^  weather.  Thus  weather  conditions  are  very  intimately 
associated  with  the  abundance  of  the  pest.  When  the  parasites 
become  abundant  they  will  often  completely  rid  a  field  of  the 
aphids  within  a  few  days.  All  of  the  common  ladybird  -beetles 
{Coccinellidoe),  Syrphus-fly  larvae,  and  lace-winged  fly  larvae 
(Chrysopidoe)    are  commonly   found   feeding   upon    the    aphids. 

Control. — No  practical  remedy  for  this  species  is  known  nor 
are  means  of  control  easily  suggested.  The  suppression  of 
volunteer  wheat  and  oats  m  early  fall  will  prevent  the  multiplica- 
tion of  the  pest  before  fall-sown  wheat  is  available,  and  the  late 
sowing  of  wheat  in  the  fall  will  reduce  the  numbers  entering 
hibernation.  A  wise  rotation  and  the  thorough  preparation 
of  the  seed-bed  and  liberal  fertilization  will  be  of  value  in  avoid- 
ing injury  in  the  same  way  as  has  been  described  for  other  pests 
of  small  grains.  Fortunately  this  species  rarely  does  very  wide- 
spread injury  and  its  parasites  usually  soon  bring  it  under  control. 

The  Spring  Grain-aphis  or  Green  Bug  * 

Though  long  known  as  a  serious  pest  of  small  grains  in  Europe, 
this  aphis  has  done  widespread  injury  in  this  country  only  during 
the  past  ten  years.     Though  it  occurs  throughout  the  territory 

*  Toxoptera  giaminum  Rond.     Family  Aphididce. 


138         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


north  of  latitude  41°,  with  the  exception  of  the  North  Atlantic 
States,  as  far  west  as  longitude  105°,  the  worst  injury  has  been  done 
in  northern  Texas,  Oklahoma,  and  Kansas,  though  it  has  also  been 
injurious  in  the  Carolinas  and  Tennessee. 

The  habits  of  the  insect  during  the  winter  have  not  been  suffi- 
ciently studied  to  speak  authoritatively,  but  it  seems  probable 
that  it  normally  passes  the  winter  in  the  egg  stage,  the  small  shin- 
ing black  eggs,  one-fortieth  inch  long,  being  laid  on  the  leaves  in 
the  late  fall.  In  the  South,  however,  it  often  continues  to 
reproduce  throughout  the  winter,  and  with  a  mild  winter  the 
numbers  so  multiply  that  unless  checked  by  parasites  serious 
injury  is  done  by  late  winter  or  early  spring.  Both  wingless  and 
winged  forms  occur  throughout  the  year.     The  wingless  female 


Fig.  118. — The  spring  grain-aphis  or  "green  bug"  (Toxoptera  grarmnum): 
a,  winged  migrant;  h,  antenna  of  same,  a,  much  enlarged;  h,  highly- 
magnified.     (From  Pergande,  U.  S.  Dept.  Agr.) 

is  from  one-twenty-fifth  to  one-fourteenth  inch  long,  yellowish- 
green,  with  a  median  line  slightly  darker,  eyes  and  most  of  the 
antennae  black,  of  the  shape  shown  in  Fig.  119.  The  winged 
female  is  slightly  larger,  with  a  wing  expanse  of  about  one- 
quarter  inch,  and  of  the  same  general  coloration,  except  that  the 
head  is  brownish-yellow  and  the  lobes  of  the  thorax  are  blackish. 
The  aphids  hatching  from  the  eggs  are  all  females,  which  give 
birth  to  live  young,  no  male  forms  occurring  during  the  summer. 
During  her  life  of  slightly  over  a  month  a  female  will  give  birth  to 
50  or  60  young,  which  commence  to  reproduce  in  the  same  manner 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


139 


when  about  seven  da3^s  old,  so  the  numbers  of  the  pest  obviously 
increase  with  enormous  rapidity,  and  with  thousands  of  tiny  beaks 
pumping  out  the  sap  the  young;  grain  plants  soon  succumb.  The 
rate  of  reproduction  and  growth  is,  of  course,  much  slower  in 
colder  weather,  the  above  being  the  average  for  the  growing  season. 
Thus  in  an  open  winter  the  aphids  will  continue  to  multiply,  and 
by  February,  in  northern  Texas,  small  spots  of  wheat  and  oats 
will  show  the  effect  of  their  work,  by  March  the  injury  may  become 
widespread  and  serious,  and  b}^  the  middle  of  April  the  crops  may 
be  ruined.     As  the  aphids  become  excessively  abundant  and  the 


Fig.  119. — Toxoptera  graminum:  a,  newly  born,  and  b,  adult  wingless  green 
bug,  greatly  enlarged.     (After  S.  J.  Hunter.) 

food  supply  disappears,  almost  all  develop  wings,  and  immense 
clouds  of  the  winged  females  are  carried  northward  by  the 
winds,  so  that  an  outbreak  in  earh^  spring  in  the  South  leads  to  an 
infestation  farther  north,  and  excessive  multiplication  will  again 
carry  the  pest  still  northward,  progressing  in  that  direction  as  it 
increases  during  the  season,  rather  than  being  spread  at  one  time. 
Thus  in  1907  it  became  abundant  in  Oklahoma  in  April,  in  Kansas 
in  May,  and  by  July  it  was  found  in  Minnesota,  where  it  rarely 
occurs  and  does  no  damage.     With  the  maturing  of  wheat  and  oats 


140 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


the  aphids  migrate  to  various  grasses,  being  particularly  fond  of 
Kentucky  blue-grass,  and  may  subsist  on  corn,  on  which  they 
may  feed  until  oats  and  wheat  are  available  in  the  fall.  Oats  is  the 
favorite  food,  and  outbreaks  of  the  pest  have  always  been  worst 
where  volunteer  oats  is  generally  grown,  the  aphids  increasing 
on  it  in  the  early  fall  and  winter  and  later  spreading  to  wheat. 
By  October  15th  in  Minnesota  and  by  early  November  in  Kansas 
the  true  winged  males  and  wingless  egg-laying  females  have  been 
observed,  but  strangely  enough  they  have  only  been  secured  in 
small  numbers  by  being  reared  in  the  laboratory,  and  have  not 
been  observed  in  the  field,  so  that  although  these  females  laid  eggs 


Fig.  120. — Lysiphlebus  testaceipes  Cress.,  adult  female  and  antenna  of  male  — 
greatly  enlarged.     (After  Webster,  U.  S.  Dept.  Agr.) 

freely  on  the  leaves  of  grain,  we  do  not  know  whether  they  are 
essential  or  not  to  the  life  history  of  the  insect  in  the  field,  for 
while  the  eggs  are  being  produced  other  females  continue  to  give 
birth  to  live  young  until  the  cold  of  winter,  and  they  have  been 
observed  to  reproduce  with  a  daily  mean  temperature  barely 
above  freezing. 

Natural  Control. — The  natural  control  of  this  most  destructive 
pest  involves  a  most  interesting  relationship  between  temperature 
and  development  of  the  parasites  which  check  its  development. 
"  The  '  green  bug '  in  normal  years  —  that  is,  when  its  breeding 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


141 


begins  in  spring  —  is  effectively  held  in  check  by  its  natural  ene- 
mies, and  notably  by  a  minute,  black  wasp-like  insect,  Lysiphlebus 
testaceipes  Cress.  (Fig. 
120),  that  deposits 
eggs  singly  in  the 
'green  bugs, '  the 
grubs  hatching  from 
the  eggs  feeding  in- 
ternally on  the  bug 
and    destroying     i  t 

(Figs.  122-123).  Other  ^      io,      r     •  m  ,,  -,   ■       ,    (a 

,  .  Fig.  121. — L?/sip/jZe6MS  parasite  in  act  of  depositing 

natural    enemies    are      eggs  in  thebody  of  a  grain-aphis— much  enlarged, 
the  larva   of  certain      (After  Webster;  U.  S.  Dept.  Agr.) 

predaceous  flies,  and  the  larvae  and  adults  of  lady-beetles.     The 

little  wasp-like  parasite  first  mentioned, 
however,  is  the  one  that  keeps  the  '  green 
bug'  in  control  in  normal  years,  and  in 
years  when  the  latter  is  most  abundant 
finally  over-comes  it,  as  was  the  case  in 
1907  in  Kansas,  North  Carolina,  and  other 
States  in  the  more  northern  part  of  the 
range  of  the  pest." 

"Unfortunately  this  parasitic  "wasp" — 
as  with  other  beneficial  insects — is  active 
only  while  the  temperature  is  above  56°  F., 
or  at  least  10°  above  that  at  which  the 
'green  bug'  breeds  freely;  and  herein  is  the 
whole  secret  of  the  irregular  disastrous  out- 
breaks of  the  'green  bug'  in  grain  fields. 
As  accounting  for  the  outbreak  in  the  year 
1907,  the  'green  bug'  had  had  a  whole 
winter  and  the  following  late  sprmg  in 
which  to  breed  and  multiply  unmolested, 
and  it  accomplished  its  principal  damage, 
as  in  Texas  and  southern  Oklahoma,bef  ore 
the  weather  was  warm  enough  for  the  para- 
siteto  increase  sufficiently  to  overcome  it." 


illJl 


Fig.  122.— Dead  "green 
bugs,"  showing  hole 
from  which  the  matu- 
red parasite  of  Lysiph- 
lebits  emerges.  The 
top  figure  shows  the 
lid  still  attached,  but 
pushed  back;  the  bot- 
tom figure  shows  the 
parasite  emerging. 
Enlarged.  (After 
Webster,  U.  S.  Dept. 
Agr.) 


"As  further  illustrative  of  the  import- 
ant bearing  of  weather  conditions,  it  is  found  that  in  the  case  of 
the  three  important  outbreaks  of  this  insect,  namely,  for  the  years 


142  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


1890,  1901,  and  1907,  the  temperature  for  the  first  five  months  of 
each  of  these  years,  m  eluding  the  latter  part  of  the  winter  and 
spring,  was  above  the  normal  for  the  winter  months  and  below  the 

normal  for  the  spring  months;  in  other 
words,  warm  winters  and  cold,  late 
springs." 

"  The  little  parasitic  wasp  which  is 
so  useful  in  the  control  of  this  pest  is 
native  to  this  country,  widely  dis- 
tributed, and  every  year  does  its  work 
with  the  '  green  bug  '  and  with  other 
aphids.  It  is  always  present  in  grain 
fields,  as  shown  by  its  appearance 
every  year,  tc  war  on  these  pests  when- 
ever the  weather  conditions  make 
its  breeding  and  multiplication  pos- 
sible, and  its  rate  of  breeding  is  so 
rapid  (there  being  a  generation  about 
every  ten  days)  that  with  a  week  or 
two  of  favorable  weather  it  gains  con- 
trol over  its  host  insects  and  destroys 
them.* 

Control.  —  Most  important  of  all 
methods  of  control  is  the  abandonment 
of  the  growing  of  volunteer  oats  and 
the  destruction  of  all  volunteer  oats 
and  wheat  in  the  early  fall.  Uni- 
versal experience  throughout  the  in- 
jured area  shows  that  relatively  little 
injury  occurs  where  volunteer  oats 
is  not  grown. 

Where  small  spots  of  grain  have  been  injured  by  the  pest  in  late 
winter,  which  is  the  way  an  outbreak  usually  begins  in  southern 
localities,  the  aphids  on  these  small  spots  may  be  killed  by  spray- 
ing with  10  per  cent  kerosene  emulsion,  or  whale-oil  soap,  5  pounds 
to  a  barrel  of  water,  by  covering  the  spots  with  straw  and  burning 
or  by  plowing  under  the  infested  spots.  Were  this  generally  done 
before  the  aphids  commence  to  multiply  rapidly,  it  is  entirely 
possible  that  widespread  injury  might  be  averted. 

*  From  F.  M.  Webster,  Circular  93,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


k 


<jai 


Fitj.  l_'o.  r:iij-;iaz(jd  green 
bugs — enlarged.  (From  photo- 
graph, after  S.  J.  Hunter.) 


CHAPTER  IX. 

INSECTS  INJURIOUS  TO  CORN 

The  Western  Com  Root-worm  * 

Throughout    the  corn  States  of  the  northern  Mississippi  Val- 
ley, wherever  corn  is  grown  upon  the  same  land  it  is  subject  to 
serious  injury  by  the  Western  Corn  Root-worm,  so  called  because 
it  first  became  injurious 
in   Missouri    and    Kan- 
sas and  gradually  spread 
eastward    to   Ohio, 
though     not   injurious 
south  of  the  Ohio  River. 
Though  the  life  history  of 
the  insect  has  not   been 
entirely  determined,  the 
following  summarizes  it 
as  observed  by  Professors 

S.A.Forbes  and  F.   M.  ^'^-  P^tT^*^    ^^'^^''^    corn    root-worm:    a 

beetle;  o,  larva;  c,  enlarged  leg  of  same;  d, 
Webster  in    Illinois    and       pupa— all  enlarged.     (After  Chittenden,  U.  S. 

Indiana.      The  eggs  are      ^^P^-  ^S''-) 

laid  in  the  early  fall,  within  a  few  inches  of  the  base  of  the  stalk, 

and  just  beneath  the  surface  of  the  soil.     The  egg  is  a  dirty  white 

color,  oval  in  shape,  and  about  one-fiftieth  inch  long.     The  winter 

is  passed  in  the  egg  stage,  differing  from  most  nearly  related  beetles 

in  this,  and  the  eggs  hatch  in  the  spring  or  early  summer.     At  first 

the  larvse  eat  the  small  roots  entire,  but  later  burrow  under  the 

outer  layers  of  the  larger  roots,  causing  the  stalks  on  rich  loam  to 

be  easily  blown  over,  or  dwarfing  the  plant  on  poorer  land  so  that 

it  produces  but  small  ears.     The  full-grown  larva  is  nearly  white 

with  a  brown  head,  a  little  less  than  one-half  inch  long   by   about 

one-tenth  inch  in  diameter.     Three  pairs  of  short  legs  are  found 

*  Diabrotica  longicornis  Say.     Family  Chrysomelidoe.      (See  F.  M.  Webster, 
U.  S.  Dept.  Agr.  Bulletin  No.  8.) 

143 


144  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

on  the  thorax,  but  otherwise  the  body  appears  perfectly  smooth 
to  the  eye,  though  finely  wrinkled.  Before  pupation  the  color 
becomes  slightly  darker  and  the  body  shortens.  Leaving  the 
roots,  the  larvae  then  form  small  oval  cells  in  the  soil  and  in  them 
transform  to  pupse,  from  which  the  adult  beetles  emerge  in  a 
short  time.  The  beetles  appear  from  the  middle  of  July  on 
through  August,  about  two  months  being  required  for  development 
after  hatching  from  the  egg.  The  beetles  are  of  a  greenish  or 
greenish-yellow  color,  about  one-quarter  inch  long,  and  resemble 
the  common  striped  cucumber-beetle  (page  340)  in  form.  They 
are  to  be  found  in  the  corn-fields  feeding  upon  pollen  and  silk 
until  the  latter  becomes  dry,  and  lay  their  eggs  during  August 
and  September.  The  beetles  are  often  found  feeding  upon  various 
weeds,  clover,  beans,  cucumber  and  squash  vines,  and  the  blossoms 
of  thistle,  sunflower  and  golden  rod. 

Control — As  the  larvae  feed  only  on  corn,  if  the  corn-field  be 
planted  to  some  other  crop,  starvation  results,  and  a  simple  rota- 
tion in  which  corn  is  not  allowed  on  the  same  land  for  over  two 
years  in  succession  usually  prevents  injury,  though  a  field  in  which 
injury  has  occurred  should  be  planted  to  some  other  crop  at  once. 
It  is  imprudent  to  plant  corn  on  fields  in  which  the  beetle  has  been 
observed  feeding  in  large  numbers  on  clover  and  weeds  during  the 
late  fall  of  the  previous  year.  The  liberal  use  of  manure  and  fer- 
tilizers, and  thorough  cultivation  will,  of  course,  be  of  service  in 
enabling  the  plants  to  withstand  attack. 

The  Southern  Corn  Root-worm  * 

Closely  related  to  the  last  species,  but  with  somewhat  different 
habits,  the  Southern  Corn  Root-worm  is  frequently  injurious  to 
corn  from  Maryland  and  southern  Ohio  southward. 

The  adult  beetle  is  of  a  bright  green  marked  with  twelve  black 
spots,  which  have  given  it  the  name  of  12-spotted  Cucumber- 
beetle  to  distinguish  it  from  the  Striped  Cucumber-beetle  (page  340), 
with  which  it  is  often  associated  feeding  on  cucurbs.  It  is  some- 
what larger  and  more  robust  than  D.  longicornis,  and  is  almost 
omnivorous  in  its  food  habits,  feeding  upon  the  foliage  and  flowers 
of  a  long  list  of  forage  and  garden  crops,  to  which  it  often  does 
considerable  damage.  Beans  are  frequently  injured  in  much  the 
*  Diabrotica  12-punctata  Oliv.     Family  Chrysomelidoe. 


INSECTS  INJURIOUS  TO  CORN 


145 


same  way  as  corn  and  the  roots  of  melons  and  other  cucurbs  are 
often  so  riddled  by  the  larvas  as  to  kill  the  plants. 

Injury  to  corn  is  done  by  the  larvw  in  the  spring, when  they  feed 
upon  the  roots  while  the  corn  is  but  a  few  inches  high,  bore  into  the 
crown,  and  boring  into  the  base  of  the  stalk  through  the  young 
leaves  eat  out  the  "  bud."  The  latter  injury  often  seems  to  be 
more  serious  to  corn  than  the  injury  to  the  roots,  and  has  given 
the  insect  the  common  local  name  of  ^'  budworm,"  which  is 
unfortunately  applied  to  several  other  insects  which  do  similar 
injury.  Larvae  have  been  found  attacking  wheat,  rye,  millet  and 
Johnson  grass  in  a  similar  way,  the  beetles  seeming  to  be  attracted 
to  fields  containing  Johnson  grass  before  the  corn  appears,  thus 


FiQ.  125. — ^The  southern  corn  root-worm:  a,  egg;  h,  larva;  c,  work  of  larva 
at  base  of  cornstalk;  d,  pupa;  e,  beetle — all  much  enlarged  except  c. 
(After  RUey.) 

injuring  such  grassy  fields  more  severely.     Injury  to  corn  seems  to 
be  worse  on  low,  damp  spots. 

Life  History. — The  beetles  hibernate  over  winter  and  are 
among  the  first  insects  to  appear  in  early  spring,  appearing  by  the 
middle  ot  March  in  the  Southern  States.  Eggs  are  laid  during  April 
in  the  Gulf  States  and  from  late  April  to  early  June  in  Kentucky 
and  the  District  of  Cokunbia.     The  egg  is  dull  yellow,  oval,  and 


146  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

about  one-fortieth  inch  long.  The  eggs  are  laid  singly  just  beneath 
the  surface  of  the  soil  and  hatch  in  from  seven  to  ten  days,  those 
laid  early  in  the  season  requiring  considerably  longer.  The 
larvsG  become  full  grown  and  pupate  about  a  month  later,  the 
adult  beetles  of  the  first  generation  appearing  during  May  and 
early  June  in  the  Gulf  States  and  in  late  June  and  early  July  in  the 
District  of  Columbia  and  Kentucky.  Thus  the  complete  life  cycle 
requires  from  six  to  nine  weeks  in  the  spring.  Eggs  are  laid  by  the 
first  generation  of  beetles,  the  larvae  being  found  on  the  roots  of 
corn  from  midsummer  until  fall,  when  the  second  generation  of 
beetles  is  found  in  October  and  November  in  Kentucky.  In  the 
Gulf  States  there  are  undoubtedly  three  complete  generations, 
though  they  have  not  been  carefully  followed.*  The  beetles 
assemble  in  the  late  fall  on  clover  and  alfalfa  upon  which  they  feed 
until  winter  sets  in,  and  often  come  out  and  feed  during  warm 
spells  in  January  and  February  in  the  Southern  States. 

Control. — Although  rotation  of  crops  will  not  be  as  effective  in 
the  control  of  this  species  as  in  the  case  of  D.  longicornis,  it  will 
undoubtedly  be  found  of  value  to  avoid  planting  corn  in  succession 
where  injury  is  probable.  By  planting  late,  after  the  beetles  have 
laid  their  eggs,  injury  has  been  avoided  in  Georgia.  Liberal  seed- 
ing, using  ten  grains  of  seed  per  hill,  will  give  a  sufficient  stand 
free  from  attack,  so  that  by  thinning  a  good  stand  may  be  secured. 
Fields  which  are  well  infested  with  Johnson  grass,  or  other  thick- 
stemmed  grasses,  should  be  avoided,  for  as  already  indicated  the 
beetles  will  be  attracted  to  them  before  the  corn  is  up.  Both 
on  account  of  the  feeding  habits  of  the  larvae  and  the  migratory 
habits  of  the  beetles  no  insecticide  treatment  commends  itself  as 
practicable. 

The  Com-root  Webworm  t 

Injury. — When  young  corn-plants  are  seen  to  stop  growing, 

become  deformed,  and  to  die  off  in  such  numbers  as  to  frequently 

necessitate  replanting,  upon  examination  of  the  roots  the  injury 

will  sometimes  be  found  to  be  due  to  the  work  of  a  small  caterpillar. 

Two  or  three,  very  often  five  or  six,  and  sometimes  as  many  as 

*  In  the  Northern  States,  where  this  species  is  not  a  pest  of  'corn,  but  is 
common  on  cucurbs  and  garden  plants,  there  is  probably  but  a  single  genera- 
tion with  a  life  history  very  similar  to  that  of  the  striped  cucumber-beetle, 
which  see. 

t  Crambus  caliginosellus  Clem.     Family  Crambidce. 


INSECTS  INJURIOUS  TO  CORN 


147 


eight  or  nine,  will  be  found  at  the  base  of  a  plant  about  an  inch 
below  the  surface  of  the  soil,  and  not  over  4  to  6  inches  from 
the  stalk,  usually  be- 
ing in  close  proximity 
to  it.  If  each  larva 
is  covered  with  a  fine, 
loose  web,  to  which 
cling  particles  of 
earth  forming  a  sort 
of  case,  it  is  probably 
a  corn-root  web- 
worm. 

Where  the  web- 
worms  are  present  in 
any  number  they  will 
often  necessitate  a 
second,  third,  or 
sometimes  a  fourth 
planting,  making  the 
corn  very  late  and  in- 
volving considerable 
expense.  The  worms 
bore  into  the  young 
stalks  just  above  the 
ground,  frequently 
cutting  them  off  en- 
tirely. Later  on  the 
larger  stalks  are 
gouged  out  at  or 
slightly  above  the 
surface  of  the  ground, 
and  the  larvae  burrow 
into  the  folded  leaves, 
which  when  they  unfold  have  several  transverse  rows  of  three  to 
five  holes.  On  account  of  this  habit  these  insects  are  sometimes 
known  as  "  bud  worms."  Strong  plants  will  often  make  a  new 
start  and  survive  the  injury,  but  remain  much  behind  those  not 
attacked,  while  most  of  the  weaker  plants  will  decay  and  rot  off. 


Fig.  126. — The  corn-root  web-worm  (Crambus 
caliginosellus):  a,  larva;  6,  pupa;  c,  moth;  d, 
segment  of  larva;  e,  parasite.     (After  Johnson.) 


148         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Moth. — As  one  walks  through  pasture  or  grass  land, 
many  little  white  and  yellowish  moths  are  seen  flying  about 
on  all  sides,  but  quickly  disappear  as  they  alight  on  the  grass. 
If  a  single  individual  be  watched  more  closely,  it  will  be  noticed 
that  in  alighting  upon  a  blade  of  grass  it  quickly  rolls  its  wings 
very  tightly  around  its  body,  and  hugs  up  close  to  the  grass 
so  that  it  is  hardly  distinguishable  from  it.  Projecting  from  the 
head  in  front  is  what  appears  to  be  a  long  beak  or  snout,  on 
account  of  which  these  moths  are  often  known  as  "snout  moths," 
but  which  really  consists  of  the  palpi  or  feelers.  The  "  grass- 
moths,"  as  they  are  sometimes  called,  belong  to  the  genus  Crambus 
and  include  several  common  species,  which  are  marked  with  silver 
stripes  and  bands,  as  well  as  golden  lines  and  markings,  so  that 
they  often  present  a    very    handsome   appearance. 

Life  History. —  These  are  the  parents  of  the  web-worms  which 
do  so  much  injury  to  the  young  corn-roots,  the  principal  depreda- 
tors upon  corn  belonging  to  the  species  Crambus  caliginosellus. 
They  lay  their  eggs  in  grass  land  in  May  or  early  June,  dropping 
them  on  the  surface  among  the  rubbish  or  vegetation,  or  attaching 
them  to  the  grass.  They  are  oval  in  form  and  of  a  yellowish  color, 
each  being  marked  with  regularly  placed  ridges.  About  two  hun- 
dred eggs  are  laid  by  each  female.  In  from  six  to  ten  days  the 
eggs  hatch.  The  young  larvae  soon  form  their  loose  silken  webs 
or  tubes  at  or  a  little  below  the  surface  of  the  soil,  burrowmg 
among  the  roots,  and  feeding  upon  the  stalk  and  outer  leaves, 
or  kilhng  the  plant  by  attacking  the  crown.  The  larvae  vary 
considerably  in  color,  from  a  yellowish  white,  through  pink, 
to  a  reddish  or  brownish  shade,  and  are  studded  with  small 
tubercles,  each  bearing  a  tuft  of  bristly  hairs.  The  larvae  become 
full  grown  in  from  five  to  seven  weeks  and  are  then  from  one- 
haK  to  three-fourths  of  an  inch  long.  During  the  latter  part  of 
July  they  form  cocoons,  sometimes  in  the  larval  tubes,  in  which 
they  pass  the  pupal  stage  and  from  which  the  moths  emerge 
some  twelve  to  fifteen  days  later.  Eggs  are  laid  for  another 
brood  in  grass  lands  during  August  and  September,  the  larvae 
hatching  in  September  and  October  and  becoming  partly  grown 
before  winter.  They  hibernate  in  their  webs  over  winter,  and  as 
soon  as  the  grass  commences  its  growth  in  the  spring  they  are 
to  be  found  feeding  upon  it,  becoming  full  grown  early  in  May. 


INSECTS  INJURIOUS  TO  CORN  149 

Preventive. — As  the  natural  food  of  these  insects  is  grass,  it 
is  not  surprising  that  corn  planted  on  sod  land  should  be  worst 
injured;  and  though  the  injury  done  the  grass  may  not  have  been 
noticeable,  when  the  available  food  is  so  greatly  diminished  by 
substituting  for  grass  the  comparatively  few  hills  of  corn  the 
injury  becomes  much  more  serious  and  apparent.  Though  the 
planting  of  corn  on  sod  land  is  a  most  common  practice,  injury 
by  this  and  many  other  insect  pests  of  corn — most  of  whose 
native  food  is  grass — might  be  avoided  by  planting  any  other 
crop  than  a  grain,  such  as  potatoes.  Otherwise  plowing  late  in 
the  fall  and  harrowing  so  as  to  expose  the  larvae  to  the  weather, 
or  plowing  so  deeply  that  they  will  be  buried  so  that  they  cannot 
regain  the  surface,  will  do  much  to  prevent  injury  the  next  season. 
Inasmuch  as  the  moth  will  not  lay  her  eggs  upon  plowed  land 
if  the  land  be  plowed  early  she  will  be  driven  to  other  fields; 
but  the  exact  time  of  oviposition  varies  for  different  latitudes. 

Generous  fertilization  will  aid  the  plants  in  overcoming 
injury  very  considerably.  Dr.  J.  B.  Smith  advises  "  the  applica- 
tion of  all  the  necessary  potash  in  the  form  of  kainit,  put  on  as 
a  top-dressing  after  the  field  is  prepared  for  planting,"  and  says: 
"Fall  plowing  and  kainit  as  a  top-dressing  in  spring  will,  I  feel 
convinced,  destroy  by  all  odds  the  greater  proportion  of  the  web- 
worms  that  infest  the  sod,  and  would  also  destroy  or  lessen  many 
other  pests  which  trouble  corn  during  the  early  part  of  its  life." 

The  Cora-root  Aphis  * 

Where  patches  of  corn  become  dwarfed,  the  leaves  becoming 
yellow  and  red,  with  a  general  lack  of  vigor,  the  grower  may  well 
be  suspicious  of  the  presence  of  the  Corn-root  aphis.  These 
little  aphids,  which  cluster  on  the  roots  of  corn,  are  a  bluish- 
green  color,  with  a  white  waxy  bloom,  and  of  the  form  shown  in 
Fig.  127.  Two  short,  slender  tubes  project  from  the  posterior 
part  of  the  abdomen  which  are  commonly  called  honey-tubes, 
because  they  were  formerly  supposed  to  give  out  the  honey-dew, 
which  is  so  relished  by  the  ants  which  tend  the  aphids  to  secure 
it.  The  winged  female  has  a  black  head  and  brownish-black 
thorax,  with  pale  green  abdomen  bearing  three  or  four  blackish 

*  Aphis  maidi-radicis  Forbes.     Family  Aphididae. 


150  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

marginal  spot.s  and  small  dark  specks  over  the  surface.     The 
antennae  are  dark  and  the  legs  blackish. 

The  corn-root  aphis  occurs  throughout  the  principal  corn- 
growing  States,  but  has  been  most  destructive  where  corn  is 
most  extensively  grown  and  is  often  planted  year  after  year 
on  the  same  land.  Dr.  Forbes,  to  whom  we  are  indebted  for 
most  of  our  knowledge  of  this  pest,*  has  observed  fields  of* 
corn  in  Illinois  planted  in  corn  for  the  second  season  totally  ruined 
by  the  root-aphis.  Broom-corn  and  sorghum  are  the  only  other 
cultivated  crops  which  have  been  injured,  but  the  list  of  food 


Fig.  127. — The  corn  root-aphis  (Aphis  maidi-radicis  Forbes):  at  left,  ovip- 
arous female;  a,  hind  tibia,  showing  sensoria;  at  right,  male;  a,  antenna 
— much  enlarged.     (After  Forbes.) 

plants  includes  smartweed,  purslane,  ragweed,  foxtail,  and  crab 
grasses,  and  many  other  weeds  and  grasses  which  spring  up  in 
the  corn-field.     In  South  Carolina  Professor  A.  F.  Conradi  has 
found  it  injuring  cotton. 

*  S.  A.  Forbes,  17th,  18th,  and  25th  Reports  of  the  State  Entomologist 
of  Illinois;  Bulletin  60,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  p.  29;  Bul- 
letins 104,  130,  and  178,  Illinois  Agr.  Exp.  Sta.  [See  also  J.  J.  Davis,  Bulletin 
12,  Part  VIII,  Technical  Series,  and  U.  S.  Dept.  Bulletin  891,  Bureau  of 
Entomology,  U.  S.  Dept.  Agr.,  and  F.  M.Webster,  Circular  86,  Bureau  of 
Entomology,  U.  S.  Dept.  Agr. 


Fig.  128. — Diagram  showing  history  of  the  corn  root-aphid  and  its  relations 
with  the  cornfield  ant.  Note  that  during  the  winter  the  aphids  are  carried 
by  the  ants  below  the  frost  line,  where  the  plow  cannot  reach  them.  (After 
J.  J.  Davis,  U.  S.  Dept.  Agr.  Bulletin  891.) 

151 


152  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

If  the  nests  of  the  small  brown  ant*  so  common  in  corn-fields 
infested  with  the  root-aphis,  be  broken  open  during  the  winter, 


Fig.  129. — The  corn-root  aphis  (Aphis  madidi-radicis  Forbes):  fl,  wingless 
vivaparous  female;  a,  apex  of  abdomen;  2,  antenna  of  same;  3,  pupa; 
4,  winged  vivaparous  female;  5,  antenna  of  same.     (After  Forbes.) 

many  of  the  little  black  aphis  eggs,  which  have  been  carefully 
stored  by  the  ants,  will  be  found.  They  are  a  glossy  black  color, 
oval  in  shape,  and  will  sometimes  be  found  in  small  piles  in  the 

*  Lasius  niger  Linn.  var.  americanus  Emery.      See  Forbes,  Bulletin  131, 
Illinois  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  CORN  153 

chambers  of  the  ants'  nests.  On  warm  days  the  ants  bring 
them  up  to  the  warmer  surface  soil  and  in  cold  weather  carry 
them  far  down  into  the  unfrozen  earth.  With  the  appearance 
of  young  smartweed  and  foxtail-grass  in  April  and  May  the  eggs 
commence  to  hatch.  The  ants  at  once  lay  bare  the  roots  of 
these  plants  and  carry  their  young  wards  to  them,  where  large 
colonies  soon  become  established.  If  the  field  is  not  planted  in 
corn,  the  lice  will  feed  later  upon  the  roots  of  pigeon-grass  or 
purslane.  In  early  May  lice,  the  second  generation,  commence 
to  appear,  among  them  being  both  wingless  and  winged  forms. 
This  brood  and  all  of  these  during  the  summer  are  produced  by 
females  known  as  agamic  females,  which  give  birth  to  live  young 
without  mating  with  a  male.  As  soon  as  corn  plants  are  available 
the  ants  again  transfer  the  aphids  to  their  roots,  and  carry  any 
winged  aphids  which  may  have  spread  over  the  field  down  on 
to  the  roots  of  the  corn.  All  through  the  summer  the  ants 
attend  the  lice,  burrowing  around  the  roots  of  the  corn,  and 
carrying  them  from  plant  to  plant,  in  return  for  which  the 
aphids  give  off  the  sweet  honey-dew,  when  stroked  by  the  ants' 
antennae,  upon  which  the  ants  feed.  During  the  summer  the 
aphids  continue  to  reproduce  with  extreme  rapiditj'',  an  aphid 
maturing  and  giving  birth  to  young  about  eight  days  after  it  is  born, 
each  generation  taking  about  sixteen  days  and  there  being  about 
twelve  generations  during  the  season.  Both  winged  and  wingless 
agamic  females  occur  throughout  the  summer,  but  late  in  Sep- 
tember and  in  October  wingless  forms  which  develop  into  true 
males  and  females  are  produced.  These  mate  and  the  females 
lay  eggs  during  October,  most  of  them  being  carried  by  the  ants 
to  their  nests,  where  the  eggs  are  laid. 

Control. — Owing  to  the  fact  that  the  aphids  do  not  migrate 
until  the  second  generation,  a  rotation  of  crops  will  be  of  great 
service  in  checking  their  injuries,  as  corn  planted  on  uninfested 
land  will  not  be  attacked  until  it  has  been  able  to  secure  a  good 
start,  and  if  well  fertilized  will  be  able  to  withstand  successfully 
whatever  injury  may  occur.  Rarely  is  corn  on  land  not  in  corn 
the  previous  year  seriously  injured,  and  where  infestation  has 
not  been  serious  throughout  a  community,  it  may  usually  be 
grown  two  years  in  succession  with  safety. 


Fig.  130. — The  corn-field  ant  (Lasius  niger  americanus) :  '1,  worker;  2,  larva; 
3,  winged  male;  4,  pupa;  5,  winged  female;  6,  female  with  wings  re- 
moved.    (After  Forbes.) 

154 


INSECTS  INJURIOUS  TO  CORN  155 

THe  proper  fertilization  of  plants  affected  with  root  insects 
is  always  of  great  importance,  enabling  the  plant  to  make  a  crop 
in  spite  of  them  if  the  attack  is  not  too  severe.  Professor  F.  M, 
Webster  observes  that  land  which  has  been  fertilized  with  barn- 
yard manure  is  much  less  injured  by  this  insect  than  that  where 
commercial  fertilizers  are  used. 

As  the  ants  not  only  spread  the  pest  during  spring  and  summer, 
but  house  the  eggs  in  their  nests  over  winter,  any  means  for 
destroying  their  nests  will  be  of  importance  in  controlling  the 
aphids.  Where  it  is  practicable,  deep  plowing  in  late  fall  and 
winter,  with  thorough  harrowing,  will  break  up  the  nests,  and 
land  so  treated  has  shown  decidedly  less  injury  the  next  season. 
Similarly  plowing  deeply  and  harrowing  several  times  in  spring 
not  only  breaks  up  the  ants'  nests,  but  destroys  the  weeds  and 
grasses  upon  which  the  aphids  feed  before  corn  is  up,  and  also 
furnishes  the  best  possible  seed-bed  and  soil  conditions.  This 
should  be  particularly  thorough  in  low  spots  where  weeds  are 
thickest  and  where  the  aphids  appear  first.  Such  spring  cultiva- 
tion has  been  demonstrated  as  very  effective  in  the  control  of 
the  pest.  In  recent  years  Professor  S.  A.  Forbes  has  conducted 
experiments  in  Illinois  which  seem  to  show  that  dipping  the  seed 
in  a  repellant  such  as  a  lemon  oil  will  render  it  obnoxious  to  the 
ants,  and  thus  protect  the  hill.  This  has  not  proven  successful, 
however,  when  heavy  rains  followed  planting  and  washed  off 
the  repellant.  Lemon  oil  was  used  by  adding  1  gallon  of  wood 
alcohol  to  1  pint  of  oil  of  lemon,  of  which  3  fluid  ounces  (6  table- 
spoonfuls)  were  stirred  into  each  gallon  of  seed  used,  being  sure 
that  all  the  seeds  were  well  coated.  Such  a  treatment  cost  about 
ten  cents  per  acre  and  resulted  in  reducing  the  number  of  aphids 
89  per  cent  and  the  number  of  ants  79  per  cent,  so  that  it  may 
well  be  given  a  trial,  but  the  chief  reliance  should  be  placed  upon 
rotation  and  early  cultivation. 

The  Com  Leaf-aphis  * 

Although  the  corn  leaf -aphis  is  not  often  very  seriously 
injurious  to  corn,  in  Texas  and  other  Southern  States  it  frequently 
becomes  so  abundant  on  sorghum  and  corn,   and  in  winter  on 

*  Aphis  maidis  Fitch.  Family  Aphididoe.  See  Webster  and  Davis, 
I.e. 


156         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

barley,  as  to  do  considerable  injury.  This  species  is  also  of  interest 
in  that  it  appears  on  corn  foliage  in  midsummer  at  the  time  when 
the  numbers  of  the  root-aphis  commence  to  decrease  on  the  roots, 
and  it  was  for  many  years  thought  to  be  the  same  species.  Care- 
ful rearing  experiments  made  under  the  direction  of  Dr.  S.  A. 
Forbes  have  failed  to  show  any  connection  between  the  root- 
aphis  and  leaf-aphis,  the  aphids  from  the  roots  being  unable  to 
establish  themselves  on  the  leaves  and  those  on  the  leaves  never 
migrating  to  the  roots.* 

Dr.  Forbes  describes  the  species  in  his  twenty-third  report 
as  follows:    "  In  the  latter  part  of  the  summer  this  bluish-green 


Fig.  131. — The  corn  leaf-aphis  (Aphis  maidis  Fitch):  winged  female  —  much 
enlarged.     (After  Webster,  U.  S.  Dept.  Agr.) 

plant-louse  may  occasionally  be  found  on  the  younger  leaves, 
the  tassel,  and  the  upper  part  of  stalks  of  corn,  and  more  abun- 
dantly and  frequently  on  broom-corn  and  sorghum.  Multiply- 
ing in  place  by  the  birth  of  living  young,  which  do  not  wander 
from  their  place  of  origin,  these  leaf-lice  may  become  abundant 
enough  to  kill  the  leaves  and  to  some  extent  to  affect  the  health 
of  the  plant.  The  insect  is,  however,  rarely  seriously  injurious 
to  corn,  but  there  is  some  evidence,  .  .  .  that  it  may  prevent  the 
fertilization  of  the  kernel  by  sucking  the  sap  from  the  silk  and 
killing  it  before  it  has  performed  its  function.     Heavily  infested 

*  S.  A.  Forbes,  13th,  16th,  18th,  and  23d  Reports  of  the  State  Entomologist 
of  Illinois. 


INSECTS  INJURIOUS  TO  CORN  157 

corn  leaves  turn  yellow  or  red,  and  may  shrivel  and  die,  partic- 
ularly if  the  weather  be  dry  at  the  time.  Broom-corn  is  consider- 
ably damaged  by  a  reddened  discoloration  of  the  brush,  due  to  a 
bacterial  affection  following  upon  the  plant-louse  punctures. 

"The  wingless  form  of  this  aphis  about  2  mm.  (one-twelfth  inch) 
long  and  half  as  wide  at  the  widest  part,  the  body  being  somewhat 
ovate  in  outline.  The  general  color  is  pale  green,  with  the  cauda, 
cornicles  and  the  greater  part  of  the  rostrum,  antennae  and  legs 
black.  The  head  is  marked  with  two  longitudinal  dark  bands, 
and  the  abdomen  with  a  row  of  black  spots  on  each  side 
and  a  black  patch  about  the  base  of  the  cornicles.  The  latter 
are  swollen  in   the  middle,   making    the   outlines  convex. 

The  winged  form  is  somewhat  different  in  color,  the  head  being 
black  and  the  thorax  chiefly  black  above. 
The  abdomen  is  pale    green,  bluish    at        V^  / 

the  sides,   with    two   transverse  black       V      >v      j^  ^ 
bands  preceding  the  cauda,  and  the  seg-  \      iTj^     / 

ments  behind  it  edged  with  dark."    These  ^^==^.-'.~^ 

differences    between    this  and  the  root        y^^-      ■"^'f^'^%. 
aphis  are  shown  in  the    accompanying     a 
figures.       "Aphis  maidis    has    been  re- 
ported at  various  times  as  a  corn  insect 
from  New  York  to   Texas,  Minnesota 
and  California.     The  species  makes  its 

appearance  in  midsummer,  our  earliest  Fig.  132. — The  wingless 
,    ,       ,T,i.      .  ,  ,     .        T   T     r^       1  •         female    of   the    corn    leaf- 

date    (Illmois)  bemg  July  9,  when  speci-      aphis— much  eniarged. 

mens  were  found  on  young  leaves  of  corn.  (After  Webster,  U.  S.  Dept. 
We  have  no  record  whatever  to  show 

whence  it  comes  or  where  it  lives  preceding  this  time.  Having 
once  conmaenced  to  breed  on  the  food-plants  mentioned,  it  con- 
tinues there  until  freezing  weather  overtakes  it,  when,  with  the 
death  of  its  food  plants,  it  gradually  disappears,  leaving  neither 
eggs  nor  hibernating  adults  on  or  about  these  plants,  and  passing 
the  winter  we  do  not  know  how  or  where."  Its  occurrence  on  bar- 
ley in  Texas  in  January  may  throw  some  hght  upon  its  wintering 
habits  in  the  South.  "  The  latest  to  develop  in  the  field  largely 
acquire  wings,  and  as  the  sap  supply  in  the  plant  diminishes  they 
fly  away.     Wingless  females,  on  the  other  hand,   perish  on  the 


158  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


spot.  Indications  are  thus  very  strong  that  this  is  a  migrating 
species  whose  second  food  plant  is  thus  far  unknown." 

No  experiments  in  the  practical  treatment  of  this  pest  seem 
to  have  been  recorded. 

The  Larger  Com  Stalk-borer  * 

Throughout  the  South  from  Maryland  to  Louisiana  and  west- 
ward to  Kansas  more  or  less 
serious  injury  is  done  by 
large  white,  brown-spotted 
caterpillars  which  bore  into 
the  stalks.  In  spring  the 
young  caterpillars  bore  into 
the  heart  of  the  young 
plant  and  like  other  insects 
with  similar  habits  (see 
page  146)  are  known  as 
"budworms."  Later  the 
hollowing  out  of  the  stalk 
so  weakens  the  plant  that 
it  is  readily  broken  over  by 
the  wind.  Consequently  a 
loss  of  from  25  to  50  per 
cent  of  the  crop  not  infre- 
quently results  where  the 
pest  is  abundant. 

Life  History. — When  the 
caterpillars      become    full 
grown  in  the  fall  they  bur- 
row down  into  the  tap-root 
and  there  pass  the  winter 
Fig.  133.— Work  of  the  larger  corn  stalk-  in  a  small  cavity  at  or  near 
borer:    a,  general  appearance  of  stalk  in-  ^j^^  ^yj^^is^Ge  of  the  ground, 
lested  by  the  early  generation  of  borers;  .  ^ 

b,  same  cut  open  to  show  pupa  and  larval  About  the  time  the  land  is 
burrow.    (After  Howard,  U.  S.  Dept.  Agr.)  ^^^^^g   prepared  for     corn, 

from  March  15  to  April  30,  depending  on  the  locality,  the  larva 
changes  into  a  reddish-brown  pupa,  from  which  the  moth  emerges 
in  ten  days  or  more.     The  moth  is  brownish-yellow  in  color  with 


*  Diatraea  zeacolella  Dyar. 
1025,  U.  S.  Dept.  of  Agr. 


Family  Cramhidae.       See  Farmers'   Bulletin 


INSECTS  INJURIOUS  TO  CORN 


159 


wings  expanding  Ij  inches,  the  hind-wings  being  darker  and  bear- 
ing faint  markings  (Fig.  135).  The  eggs  are  laid  at  dusk  upon  the 
under  surface  of  the  leaves  of  the  young  corn,  and  hatch  in  from 
seven  to  ten  days.  The  eggs  are  flat,  scale-like,  and  placed  in  rows 
of  from  two  to  twenty-five,  slightly  overlapping  each  other.  They 
are  3-100  inch  long,  by  two  thirds  as  wide,  at  first  a  creamy-white, 
but  gradually  becoming  a  reddish  brown.  The  young  larva  bores 
into  the  stalk,  often  destroying  the  "bud,"  and  then  at  or  near  the 
ground,  where  it  burrows  upward  in  the  pith,  seldom  damaging 


Fig.  134. — a,  b,  c,  varieties  of  the  larva  of  the  larger  corn  stalk-borer;  d, 
third  thoracic  segment;  e,  eighth  abdominal  segment;  /,  abdominal 
segment  from  side;  g,  same  from  above  —  enlarged.  (After  Howard, 
U.  S.  Dept.  Agr.) 

the  stalk  above  the  third  joint.  As  the  borers  grow  they  become 
quite  active  and  frequently  leave  and  re-enter  the  stalk,  thus  mak- 
ing several  holes.  The  caterpillars  become  full  grown  in  twenty  to 
thirty  days,  and  are  about  one  inch  long,  dirty-white,  thickly  cov- 
ered with  dark  spots,  each  of  which  bears  a  short,  dark  bristle.  The 
mature  caterpillar  bores  outward  to  the  surface  of  the  stalk, 
making  a  hole  for  the  escape  of  the  adult  moth,  which  it  covers 
with  silk,  and  then  transforms  to  a  pupa  in  its  burrow.  This 
occurs  during  July,  and  the  moths  of  the  second  generation  emerge 
in  seven  to  ten  days.  The  second  brood  larvse  feed  on  the  old 
stalks,  tunneling  them  between  the  second  joint  and  the  ground, 
and  become  full  grown  about  harvest  time  when  they  go  into  winter 
quarters  in  the  root  as  above  described. 


160         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Control, — It  has  been  observed  that  late  planted  corn  is  much 
less  injured  than  that  planted  early,  but  as  it  is  more  seriously 
injured  by  some  other  pests,  late  planting  may  not  be  advisable. 
Where  corn  has  been  seriously  injured,  the  old  stalks  or  butts 

should  be  dragged  off  the 
field  and  burned  late  in  the 
fall,  thus  destroying  the 
over- wintering  borers. 
When  corn  is  stripped  for 
fodder,  the  stalks  left  stand- 
ing and  the  land  sown  in 
small  grain,  the  most  favor- 
able conditions  are  allowed 
the  borers  for  safely  passing 
the  winter  and  developing 
into  moths  which  will  fly  to 
new  fields  in  the  spring. 

A  simple  rotation  of  crops 
will  also  lessen  injury  con- 
siderably,  as  Dr.  L.  O. 
Howard  has  observed  that 


Fig.  135. — The  larger  corn  stalk-borer,  a, 
female;  b,  wings  of  male;  c,  pupai  — ■  all 
somewhat  enlarged.  (After  Howard, 
U.  S.  Dept.  Agr.) 


where  fields  which  had  been  in  corn  the  previous  year  were  dam- 
aged 25  per  cent,  those  planted  on  sod  land  were  damaged  but  10 
per  cent,  though  reasonably  close  to  land  which  had  been  in  corn. 

Bill-bugs  * 

Throughout  the  South  and  often  in  the  more  Northern  States, 
Canada,  and  the  West  the  bill-bugs  sometimes  become  serious 
enemies  of  young  corn-plants.  They  are  called  *'  bill-bugs  "  on 
account  of  the  prolongation  of  the  head,  termed  a  bill  or  snout, 
peculiar  to  all  the  weevils  or  "snout-beetles,"  by  means  of  which 
they  are  enabled  to  drill  holes  in  the  corn-stalks.  Several  species 
belonging  to  the  genus  Sphenophorus  are  commonly  injurious  to 
corn.  One  of  these,  S.  parvulus  Gjdl.,  also  attacks  small  grains 
and  timothy,  and  is  therefore  known  as  the  Grain  Sphenophorus. 
Another  species,  S.  obscurus  Boisd.,  does  considerable  injury  to 
sugar-cane  in  Hawaii.     The  adult  beetles  are  from  one-fourth  to 

*  Species  of  Sphenophorus.  Family  Calandridce.  See  S.  A.  Forbes,  23d 
Report  of  the  State  Entomologist  of  Illinois.  Also  Farmers'  Bulletin  1003, 
U.  S.  Dept.  Agr.,  and  Z.  P.  Metcalf,  N.  C.  Expt.  Sta.  Bull.,  13  Tech. 


INSECTS  INJURIOUS  TO  CORN 


161 


three-fourths  of  an  inch  long,  of  the  form  shown  in  the  illustration, 
and  are  of  a  brown  or  black  color,  marked  with  darker  longitudinal 
ridges  on  the  wing-covers.  The  larva  is  a  thick  floshy  white 
grub,  from  one-fourth  to  five-eighths  of  an  inch  long,  with  a  brown 
head  and  cervical  shield  on  the  first  segment,  and  footless. 

Life  History. — The  life  histories  of  the  different  species  are 
but  partially  known. 


Fig.  136. — Sphenophorus  ochreus,  larva,  adult,  and  work  in  roots  of  Scirpus. 
(After  F.  M.  Webster,  "  Insect  Life.") 

S.  parvulus  hibernates  over  winter  as  a  beetle,  appearing  in 
March  and  April.  The  female  punctures  the  stalk  of  wheat  or 
timothy — oats  and  barley  are  also  sometimes  attacked — a  little 
above  the  roots,  and  deposits  her  egg  in  the  cavity.  This  is  done 
in  May  or  June  or  even  up  to  July  1st.  The  larvae  are  to  be  found 
during  July,  becoming  full  grown  and  pupating  during  the  latter 
part  of  that  month.  The  larvae  will  eat  out^quite  a  cavity  in  the 
interior  of  the  stalk  or  bulb,  and  then  attack  the  roots,  thus  often 
killing  a  whole  clump  or  stool  of  small  grain  or  timothy.  The 
pupal  stage  is  passed  in  a  small  cell  in  the  earth  and  lasts  from  two 
to  three  weeks,  adult  beetles  emerging  from  the  middle  of  August 
to  the  first  of  October. 


162         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

One  of  the  species  most  injurious  to  corn  is  S.  ochreus  Lee. 
The  life  history  is  much  the  same  as  that  of  S.  parvuliis,  though 
eggs  have  been  found  as  late  as  July  30th.  The  natural  food-plant 
of  this  species,  however,  is  the  common  club-rush  {Scirpus  jiuvia- 
tilis),  the  roots  of  which  consist  of  bulbs  connected  by  smaller 
slender  roots.  The  eggs  are  deposited  in  or  about  the  roots  of  this 
rush,  never  having  been  found  on  corn.  The  bulbs  of  the  rush  are 
very  hard  and  oftentimes  as  large  as  hens'  eggs.  In  them  the 
larvae  burrow,  becoming  full  grown  and  transforming  to  pupae, 
from  which  the  adult  beetles  appear  in  August  and  September. 
When  the  rush  becomes  too  hard  for  the  beetles  they  often  attack 
a  common  reed  {Phragmites  communis),  piercing  and  splitting 
lengthwise  the  unfolded  terminal  leaves,  and  eating  out  the  suc- 
culent portions  within.  The  injury  to  corn  is  done  by  the  beetles 
while  the  corn  is  still  young,  feeding  upon  it  in  the  same  manner 
as  do  the  other  species.  "  Standing  with  the  head  downward  and 
the  feet  embracing  the  lower  part  of  the  stalk,"  says  Dr.  Forbes, 
"thej'  slowly  sink  the  beak  into  the  plant,  using  the  jaws  to  make 
the  necessary  perforation.  By  moving  forward  and  backward 
and  twisting  to  the  right  and  left,  the  beetle  will  often  hollow  out  a 
cavity  beneath  the  surface  much  larger  than  the  superficial  injury 
will  indicate."  As  the  lower  part  of  the  stalk  becomes  hardened, 
they  leave  it  for  the  terminal  portion,  and  when  the  ears  commence 
to  form  they  often  penetrate  the  husk  and  gouge  out  the  soft  cob. 
Sometimes  the  injury  thus  inflicted  is  but  slight,  merely  resulting 
in  a  puncturing  of  the  leaves  when  they  unfold,  these  holes  being 
in  a  series  across  the  leaf  resulting  from  a  single  puncture  when  the 
leaf  was  folded,  and  looking  much  like  the  work  of  the  corn-root 
web  worm;  but  when  several  beetles  attack  a  young  plant,  they 
will  either  kill  it  outright  or  so  deform  the  foliage  and  stalk  that 
no  ear  will  mature. 

Several  other  species  have  also  been  known  to  do  more  or  less 
injury  to  corn,  viz.,  S.  scoparius,  placidus,  cariosus,  sculptilis, 
and  pertinax,  but  so  far  as  known  their  habits  and  injuries  are 
much  the  same  as  of  those  already  described. 

Means  of  Control. — The  control  of  these  pests  is  rather  a  diffi- 
cult task.  *S.  ochreus,  as  in  fact  are  all  of  the  species,  is  most 
injurious  on  recently  cleared  swamp-lands,  and  usually  disappears 
as  fast  as  these  lands  are  drained  and  cultivated.  Planting  flax, 
potatoes,  or  some  crop  not  attacked  by  these  insects  for  the  first 


INSECTS  INJURIOUS  TO  CORN 


163 


crop  will  largcty  prevent  so  serious  injury  to  a  subsequent  corn 
crop.  The  burning  over  of  grass-  and  swamp-lands  infested  with 
the  beetles  will  also  be  of  considerable  value. 


The  Maize  Bill-bug  * 

Throughout  the  Southern  States  and  northward  to  Kansas 
there  has  been  more  or  less  serious  injurj^  by  a  bill-bug  which  has 


Fig.  137. — Sections  of  sugar-cane  showing  work  of  Sphenophorus  obscurus: 
a,  larva;  b,  pupa;  c,  probable  points  of  ovipoSition.  (After  Riley  and 
Howard,  "Insect  Life.") 

been  recognized  for  many  years  as  Sphenophorus  robustus  Horn. 

Recently  Dr.  F,  H.  Chittenden  has  recognized  this  insect  as  a  new 

*  Sphenophorus  maidis  Chittn.,  see  E.  O.  G.  Kelly,  Bulletin  95,  Part  II, 
Bureau  of  Entomology,  U.  S.  Dept.  Agr  See  also  W.  P.  Hayes,  Tech. 
Bulletin  6,  Kansas  Expt.  Station,  and  Farmers'  Bulletin  1003,  U.  S.  Dept. 
Agr. 


164 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


species  and  Mr.  E.  O.  G.  Kelly  has  published  a  complete  account 
of  its  hfe  history,  from  which  the  following  is  taken. 

As  will  be  seen  below  this  species  is  known  to  pass  its  entire  life 
history  upon  the  corn-plant  so  that  the  common  name  given  it 
appropriately  distinguishes  it  from  other  bill-bugs  previously 
mentioned.     It  has,  however,  been  found  feeding  and  probably 

breeding  in  swamp-grass  (Tripsacum 
dadyloides),  which  maybe  its  native 
food  plant. 

Life  History.  —  The  eggs  were 
found  in  southern  Kansas  during 
June,  laid  in  punctures  made  by  the 
female  in  young  corn-plants.  These 
egg  punctures  are  mere  slits  and  do 
not  seem  materially  to  injure  the 
plant.  The  eggs  hatch  in  from  seven 
to  twelve  days,  and  from  them 
emerge  small  footless,  dingy  white 
grubs,  with  chestnut-brown  heads, 
of  the  appearance  shown  in  Fig.  140. 
"They  at  once  begin  feeding  on  the 
tissues  of  the  young  corn  at  the  bot- 
tom of  the  egg  puncture,  directing 
their  burrow  inward  and  downward 
into  the  taproot.  AVhen  they  finish 
eating  the  tender  parts  of  the  taproot  they  direct  their  feeding 
upward,  continuing  until  full  grown,  allowing  the  lower  portion  of 
the  burrow  to  catch  the  frass  and  excrement.  This  burrowing  of 
the  taproot  of  the  young  growing  corn-plant  is  disastrous  to  the 
root  system;  .  .  .  allowing  it  to  die  or  become  more  or  less 
dwarfed."  Often  the  young  larvae  burrow  into  the  heart  of  the 
plant  and  cut  off  the  growing  bud,  thus  killing  the  top.  The 
larvae  become  full  grown  early  in  August,  when  they  are  about 
four-fifths  of  an  inch  long.  •'  The  larvae,  on  finishing  their  growth, 
descend  to  the  lower  part  of  the  burrow,  to  the  crown  of  the  tap- 
root, cutting  the  pith  of  the  cornstalk  into  fine  shreds,  with  which 
they  construct  a  cell  where  they  inclose  themselves  for  pupation." 
The  pupae  are  to  be  found  in  these  cells  in  late  August  and  early 
September,  the  pupal  stage  lasting  ten  to  twelve  days.  The  adults 


Fig.    138.— The     maize    bill-bug 

{Sphenopho7-us  rnaidis  Chittn.) 
— four  times  natural  size.  (Af- 
ter Kelly,  U.  S.  Dept.  Agr.) 


INSECTS  INJURIOUS  TO  CORN 


165 


commence  to  emerge  by  the  middle  of  August  and  continue  to  do 
so  until  the  middle  of  September.  "  Some  of  them  leave  the  pupal 
cells,  but  most  of  them  remain  there  for  hibernation."  Those  which 
emerged  disappeared  and  probably  hibernated  in  some  dense, 
coarse  grass  nearby.     Those  which  hibernated  in  the  pupal  cells 


Vk 


Adult 
Egg 


Larva 


v<s: 


o> 


Pupa 


19/4 


s2  S.-fr 


-^m 


^ 


lOP- 


I 

JH 


Fig.  139. — Diagram  representing  the  seasonal  appearance  of  the  maize  bill- 
bug  in  1914  in  Kansas.  (After  W.  P.  Hayes,  Technical  Bulletin  6, 
Kansas  Agr.  Expt.  Station.) 

emerged  the  next  spring  about  the  time  that  young  corn  was 
sprouting.  The  beetles  are  from  two-fifths  to  three-fifths  of  an  inch 
long,  of  a  dull  shining  black  color,  and  sculptured  as  shown  in 
Fig.  138.  "  The  beetles  are  rarel}^  observed  on  account  of  their 
quiet  habits  and  because  they  are  covered  with  mud — a  condition 
which  is  more  or  less  common  among  several  species  of  this  genus 


166        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


and  which  is  caused  by  a  waxy  exudation  of  the  elytra  to  which  the 

soil  adheres.  The  presence  of  the 
adults  of  this  species  in  a  cornfield  is 
made  evident  by  the  withering  of  the 
top  leaves  of  very  young  corn-plants, 
the  plants  having  been  severely 
gouged.    After  the    plants  grow    10 

Fig.  140.-Larva  of  the  maize  bill- to  ^^  inches  tall  they  do  not  kill 
bug — twice  natural  size.  (After  them,  but  gouge  out  such  large  cav- 
Kelly,  U.  S.  Dept.  Agr.)  j^-^^  -^  ^^^  ^^^^^^  ^^^^  ^^^^  ^^^^^^ 

twisted  into  all  sorts  of  shapes. 
The  attacked  plants  sucker  pro- 
fusely, affording  the  young,  ten- 
der growth  for  the  beetles  to  feed 
upon,  even  for  many  days  after 
the  non-infested  plants  have  be- 
come hard."  Injury  seems  to 
be  most  serious  on  low  land. 
Injury  by  this  species  somewhat 
resembles  that  done  by  the  larger 
cornstalk-borer  (Diatraea  zeaco- 
lella),  but  is  easily  distinguished 
from  the  work  of  the  other  bill- 
bugs,  as  the  punctures  of  the  lat- 
ter, which  usually  form  a  row  or 
rows  of  holes  in  the  leaves  when 
they  unfold,  are  not  always  fatal 
to  the  plants. 

Control. — Inasmuch  as  most 
of  the  beetles  hibernate  in  the 
corn  stubble,  they  may  be  readily 
destroyed  by  pulling  out  and 
burning  the  stubble.  Care  must 
be  taken,  however,  to  pull  out 
the  taproot,  as  the  stalk  will  be 
liable  to  break  above  the  beetle 
and  leave  it  in  the  ground.  As 
the  infested  stalks  have  a  poor 
root  system,  they  are  easily 
pulled.     Crop  rotation   and  fall 


Fig.  141. — Corn  plant  showing  the 
result  of  attack  of  the  maize  bill- 
bug:  a,  larval  burrow  containing 
pupa  in  natural  position — reduced 
two-thirds;  b,  egg-puncture  con- 
taining egg — enlarged  (After  Kelly, 
U.  S.  Dept.  Agr.) 

plowing  are  also  of  great  value. 


INSECTS  INJURIOUS  TO  CORN 


167 


The  Lesser  Com  Stalk-borer  * 

This  small  moth  has  been  sporadically  injurious  for  many 
years  and  seems  to  be  on  the  increase  in  the  Southern  States  where 
it  is  at  times  injurious 


to  corn,  sorghums, 
wheat,  cowpeas  and 
crabgrass,  as  well  as 
other  plants  in  con- 
siderable numbers. 
Description. — The 

moth    is    a    small,   I'^ig.  142. — The  lesser  corn  stalk  borer:  larva,  greatly 

1  -1  c  enlarged.     (After  Luginbill  and  Ainslie,  L.  C.) 

brownish    gray  form  &        v  &  ,         y 

with  a  wing  expanse  of  less  than  one  inch.     The  fore  wings  of  the 

female  are  darker  than  those  of  the  male.     The  larvse  are  slender 

caterpillars,  three  quarters  of  an  inch  in  length.     Their  prevailing 

color  is  a  hght  green  with   darker  markings,  prominent  among 

which  are  brownish  transverse  bands. 


Fig.  143. — The  lesser  corn  stalk-borer:  a,  male  moth;  b,  fore-wing  of  female 
moth.    Greatly  enlarged.    (After  Luginbill  and  Ainslie,  L.  C.) 

Life  history. — Eggs  are  produced  throughout  the  summer 
and  fall  and  the  winter  is  passed  in  the  larval  or  pupal  stage. 
There  are  probably  as  many  as  four  generations  in  the  southern 
range  of  the  insect  and  fewer  in  the  North. 

*  Elasmopalpus  lignosellus  Zeller.     Family  Pyalididre. 
See  U.  S.  Dept.  Agr.  Bulletin  539,  Luginbill  and  Ainslie. 


168         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Injury. — Injury  from  these  insects  is,  as  the  name  indicates, 
due  to  their  boring  in  the  stalks  of  the  food  plant.  It  may  be 
anywhere  from  slight  to  total.  They  seem  to  prefer  crops  grown 
on  sandy  soil. 

Control. — Absolutely  clean  cultivation,  including  cleaning 
up  of  fence  rows  and  waste  places,  along  with  late  fall  plowing, 
are  recommended  as  the  best  methods  of  control. 


Fig.  144. — Map  showing  present  known  distribution  of  the  lesser  corn  stalk- 
borer  (Elasmopalpus  lignosellus)  in  the  United  States.  (After  Luginbill 
and  Ainslie,  L.  C.) 

The  Com  Ear-worm  * 

Practically  the  only  insect  injuring  the  ears  of  field-corn  and 
the  worst  insect  pest  of  sugar-corn,  is  the  ear-worm.  In  the 
extreme  South  it  is  almost  impossible  to  grow  sugar-corn  success- 
fully on  account  of  its  injury,  while  farther  north  it  largely  reduces 
the  profits  of  corn  grown  for  the  cannery,  and  destroys  a  consider- 
able percentage  of  the  kernels  of  field-corn.  It  is  a  most  cosmopol- 
itan insect,  being  found  throughout  the  United  States  and  in  many 
parts  of  the  world,  and  has  a  long  list  of  food  plants,  being  known 
as  the  tomato  fruit-worm,  tobacco  bud-worm,  and  cotton  boll- 

*  Chloridea  obsoleta  Fab.     Family  Noduidce. 

See  H.  Garman,  Bulletin  187,  Kentucky  Agr.  Expt.  Station  and  Farmers' 
Bulletin  872,  U.  S.  Dept.  Agr.) 


INSECTS  INJURIOUS  TO  CORN 


169 


worm  when  attacking  these  plants,  besides  which  it  feeds  on  beans, 
peas,  and  many  garden  crops  and  forage  plants,  such  as  cowpeas 
and  alfalfa. 

Life  History. — Along  the  Gulf  Coast  the  first  moths  appear  in 
April,  in  the  latitude  of  33°  about  the  middle  of  May,  and  in  the 
latitude  of  Delaware  and  Kansas,  early  in  June. 

The  moth  is  about  three-quarters  of  an  inch  long  with  a  wing 
expanse  of  about  1|  inches  and  is  extremely  variable  in  color  and 
markings.     Some  are  dull  olive  green  while  others  are  yellowish 


-^'■ 


ex: 


Fig.  145. — Corn  ear-worms  at  work.  The  central  cob  has  been  attacked  by 
a  nearly  full-grown  worm,  which  has  bored  through  the  husk  near  the 
middle. 

or  nearly  white  and  with  almost  no  markings.  In  the  most  typical 
moths  the  wings  are  bordered  with  dark  bands,  the  wing  veins  are 
black  and  the  fore-wings  are  spotted  with  black. 

The  eggs  are  hemispherical  in  shape,  about  one-fifteenth  inch  in 
diameter,  light  yellowish,  and  prettily  corrugated  with  ridges  as 
shown  in  Fig.  201.     Those  of  the  first  brood  are  laid  on  corn,  peas, 


170         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


beans,  or  whatever  food-plants  are  available,  and  hatch  in  three  to 
five  days,  depending  upon  the  temperature. 

The  caterpillars  of  the  first  generation  often  attack  corn  .vhen 
about  knee-high,  feeding  in  the  axils  of  the  tender  leaves,  so  that 

when  the  leaves  unroll 
they  bear  horizontal  rows 
of  holes.  The  caterpil- 
lars are  exceedingly  vari- 
able in  color,  being  from 
a  light  green  through 
rose  color  and  brown  to 
almost  black,  and  either 
striped,  spotted  or  per- 
fectly plain.  They  be- 
come full  grown  in  about 
2|  weeks  and  are  then 
about  Ij  to  1|  inches 
long.  When  done  feed- 
ing the  caterpillar  bur- 
rows 2  to  5  inches  into 
the  soil  near  the  base  of 
the  plant.  A  cell  is  then 
constructed  which  runs 
back  to  within  a  half 
inch  of  the  surface  of  the 
soil,  so  that  the  moth 
may  readily  push  off  this 
surface  soil  and  escape.  The  burrow  finished,  the  larva  retires 
to  the  bottom  of  the  cell  and  there  molts  and  enters  the  pupal. 
The  pupa  is  four-fifths  inch  long,  shining  reddish-brown. 
During  the  summer  the  moths  emerge  about  two  weeks  later, 
but  the  last  generation  in  the  fall  passes  the  winter  in  the  pupal 
stage.  Thus  the  complete  life  cycle  from  egg  to  adult  moth 
requires  slightly  over  a  month  in  midsummer,  and  from  six  to 
eight  weeks  for  the  spring  and  fall  broods. 

The  second  generation  of  moths  appears  about  the  middle 
of  July  in  the  latitude  of  Delaware  and  Kansas.  In  the  far 
South  the  second  generation  of  moths  appears  when  corn  is  com- 


FiG.  146. — Corn  ear-worm  or  cotton  boll- 
worm  (Chloridea  obsoleta) :  a,  adult  moth ; 
h,  dark  full-grown  larva;  c,  light-colored 
full-grown  larva;  d,  pupa — natural  size. 
(After  Howard,  U.  S.  Dept.  Agr.) 


INSECTS  INJURIOUS  TO  CORN  171 

ing  into  silk  and  tassel,  upon  which  the  moths  always  prefer  to 
lay  their  eggs.  As  a  result,  the  caterpillars  of  the  second  genera- 
tion of  the  South,  and  the  third  farther  North,  do  serious  injury 
to  field-corn,  gnawing  out  the  kernels  at  the  tips  of  the  ears,  and 
furnishing  favorable  conditions  for  molds  to  propagate,  which 


Fig.  147. — Corn  ear-worm.     Husk  of  ear  of  sugar-corn  torn  open,  showing 
worms  at  work  on  tip  and  hole  through  which  a  full  grown  worm  has  left. 

do  further  injury.  From  2  to  5  per  cent  of  the  corn  crop  of  the 
country,  with  a  cash  value  of  $60,000,000  to  $150,000,000,  is  thus 
destroyed  by  the  ear-worm  annually. 

The  third  generation  of  moths  appears  the  last  of  August 
in  Delaware  and  Kansas  and  gives  rise  to  the  third  brood  of 


172       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

caterpillars,  which  is  there  the  most  destructive  brood  on  field- 
corn  and  sugar-corn,  frequently  causing  a  loss  of  from  10  to  50 


Fig.  148. — Tip  of  ear  of  corn  showing  eggs  of  corn  ear-worm  on  silks.     (After 
Quaintance  and  Brues,  U.  S.  Dept.  Agr.) 

per  cent  of  the  latter  crop.  The  caterpillars  become  full  grown 
during  the  latter  part  of  September  and  change  to  pupae,  which 
hibernate  over  winter  as  already  described. 


INSECTS  INJURIOUS  TO  CORN  173 

In  the  Gulf  States  there  are  four  full  broods  and  along  the 
Gulf  Coast  there  may  be  five  or  six,  while  in  the  Northern  States 
there  are  but  two  generations,  with  possibly  but  one  in  Ontario. 

Control. — As  the  pupa  pass  the  winter  in  the  soil,  by  all  means 
the  most  satisfactory  and  practical  means  of  control  is  to  plow 
infested  land  in  late  fall  or  during  the  winter,  plowing  deeply 
and  harrowing.  This  will  break  up  the  pupal  cells,  crush  some 
of  the  pupse,  and  expose  others  to  the  rigors  of  winter  to  which 
most  of  them  will  succumb. 

The  early  planting  of  field-corn  prevents  the  moths  from  lay- 
ing their  eggs  upon  it,  as  it  will  have  passed  the  silking  stage  and 
other  fields  which  are  in  silk  will  be  preferred;  it  being  possible 
thus  to  reduce  the  injury  by  at  least  a  third  by  early  planting. 

Silks  and  foliage  of  sweet  corn  are  sometimes  poisoned  with 
arsenate  of  lead  applied  in  the  form  of  a  dust,  three  to  five  appli- 
cations being  used,  and  much  benefit  has  been  recorded  from  the 
treatment  but  it  has  not  yet  proven  practical  for  field  corn  on 
account  of  the  expense. 

The  European  Com  Borer  * 

Concerning  this  insect,  a  recent  importation  from  Europe, 
we  can  do  no  better  than  to  quote  from  Mr.  Caffrey  who,  in  his 
introduction  to  Farmers'  bulletin  1046  of  the  U.  S.  Department 
of  Agriculture,  summarizes  the  situation  as  follows: 

"  The  European  Corn  Borer  probably  is  the  most  injurious 
plant  pest  that  has  yet  been  introduced  into  this  country.  It 
is  now  known  to  be  present  in  an  area  of  about  320  square  miles 
near  Boston,  Mass.  Unless  repressed  and  restricted  it  may 
spread  throughout  the  country  and  cause  serious  and  widespread 
losses  to  the  corn  crop. 

The  larvae,  or  borers,  tunnel  through  all  parts  of  the  corn  plant 
and  destroy  or  severel}'"  injure  the  ears  and  stalks.  The  pest 
also  attacks  celery,  Swiss  chard,  beans,  beets,  spinach,  oats,  po- 
tatoes, tomatoes,  turnips,  dahlias,  chrysanthemums,  gladiolus, 
geraniums,  timothy,  and  certain  weeds  and  grasses. 

*  Pyrausta  nubialis  Hiiebner.     Family  Pyralididce. 

See  Vinal  and  Caffrev,  Bulletin  189,  Massachusetts  Expt.  Station  and 
Farmers'  Bulletin  1046,  U.  S.  Dept.  of  Agr. 


^,_^^      The 
%UROPEAN 


N  BORER 


is  the  caterpillar 

of  a  small  moth.. 


The  mbths  lay  their 
eg'g's  in  flat  masses,^^^  ^, 
on.  the  under  side^^^  A: 


The  caterpillars 
hatch  from  these  eggs  and" 
feed  at  first  on  the  leaves,tut 
soon  bore  into  the  tassels,  tlie 
stalk.the  leaf-ribs  and  theear^ 
They  live  in  th  e 
^talkb  all  winter  and 
^^  in  spring  change 
to  reddish-brown  pupae, 
hichsoon  transformi 
ain  to  moths.. 

The  pest  also  attach 

other  garden  plants.weeds, 

'  'aryer  grasses,and  lives 

rough  the  winter  in  the. 

ilks  of  th  ese  plan  ts  as 

as  in  corn, . 


Burn  All  Plants  Containing  Caterpillars. 

f 


Cornstalks,  corn  stubble, g'rasses,weeds, and  tt 
stalks  of  garden  plants  should  be  thus  destroyed  JA' 
throughout  infested  areas  during"  fall,  C)^>^    iUl 


winter  or  early  sprin^.No  other  effective 
method  is  known  for  combating'  this  pest. 


Fig.  149. — Department  of  Agriculture  warning  against  the  European    corn 
borer.     (After  CafTrey,  Farmers'  Bulletin  1046.)  — 

174 


INSECTS  INJURIOUS  TO  CORN  175 

There  are  two  generations  each  year,  so  that  multiplication 
and  spread  are  rapid,  especially  as  very  few  of  the  borers  are 
destroyed  by  natural  enemies.  The  winter  is  passed  in  the  larva 
or  borer  stage  within  infested  plants. 

To  suppress  this  pest  burn  or  otherwise  destroy  during  the 
fall,  winter,  or  spring  all  cornstalks,  corn  stubble,  crop  remnants, 
and  stalks  of  garden  plants,  weeds,  or  wild  grasses  within  the 
infested  areas  Hkely  to  harbor  the  overwintering  borers.  Work  of 
this  kind  is  now  being  conducted  by  the  Federal,  State,  and  local 
authorities,  and  the  hearty  cooperation  of  all  property  owners, 
tenants,  or  other  interested  persons  is  earnestly  solicited.  This 
work  must  be  done  very  thoroughly.  The  borers  in  a  few  over- 
looked plants  may  increase  by  the  end  of  the  season  to  as  many 
as  were  present  before  the  clean-up. 

To  prevent  the  spread  of  the  insect,  quarantine  measures, 
both  Federal  and  State,  must  be  strictly  enforced  to  prevent 
shipment  of  infested  plants  or  plant  products  out  of  the  area 
now  infested. 

Since  the  date  of  this  bulletin  (April,  1919)  the  borer  has  been 
found  in  New  York  State,  an  area  of  400  square  miles  near  Schen- 
ectady having  been  found  to  be  infested. 

Since  little  work  has  been  done  on  the  insect  in  this  country 
except  through  the  U.  S.  Bureau  of  Entomology  we  give  here  also 
a  copy  of  the  posters  summarizing  the  apperance  of  the  injury, 
just  as  they  were  sent  out  by  the  bureau.  It  is  impossible  to 
predict  how  rapidly  the  insect  will  spread  or  how  well  it  will  adapt 
itself  to  our  conditions.  It  can  be  said,  however,  that  it  is  poten- 
tially the  most  serious  pest  which  has  ever  threatened  the  corn 
of  the  country. 


CHAPTER  X 


INSECTS  INJURIOUS  TO  STORED  GRAINS  * 

The  farmer  who  stores  his  grain,  awaiting  a  higher  price, 
is  sometimes  sadly  disappointed  to  find  that  it  has  been  so  riddled 
by  "weevil "  that  it  brings  no  more  than  had  it  been  sold  previously. 

The  term  "weevil"  is  rather  a  comprehensive  one,  being 
commonly  applied  to  almost  every  insect  infesting  stored  food- 
products.  Only  a  few  species  are  commonly  injurious  in  the 
farm  granary. 

Grain-weevils 

Of  these  the  Granary-weevil  f  and  the  Rice- weevil  {  (Fig, 
150),  are  the  most  common  and  widely  distributed.     Both  of 

these  insects  have  in- 
fested grain  from  the 
most  ancient  times,  so 
long,  in  fact,  that  the 
granary-weevil  has  lost 
the  use  of  its  wings  and 
remains  entirely  in- 
doors. They  are  small, 
brown  beetles,  from 
one-eighth  to  one-sixth 
of  an  inch  in  length, 
with  long  snouts  which 
are  of  great  service  in 
boring  into  the  kernels 
of  grain.  By  means  of 
them  the  females  punc- 
ture the  grain  and  then 
insert  an  egg  in  the 
cavity.  The  larva 
Dean,  Bulletin 


Fig.  150. — The  grain  weevil  {Calandra  granaria) : 
a,  beetle;  b,  larva;  c,  pupa;  d,  the  rice  weevil 
(C.  onjza:  beetle — all  enlarged.  (After  Chit- 
tenden; U.  S.  Dept.  Agr.) 


*  See  Farmers'  Bulletin  1029,  U.  S.  Dept.  Agr.,  and  G.  A 
189,  Kansas  Agr.  Exp.  Station, 
t  Calandra  granaria  Linn. 
X  Calandra  oryzce  Linn.     Family  CalandridcE. 


176 


INSECTS  INJURIOUS  TO  STORED  GRAINS 


177 


hatching  from  this  is  without  legs,  somewhat  shorter  than  the  adult, 
white  in  color,  and  of  a  very  robust  build,  being  almost  as  broad 
as  long.  It  soon  devours  the  soft  interior  of  the  kernel  and  then 
changes  to  a  pupa,  from  which  the  adult  beetle  emerges  in  about 
six  wrecks  from  the  time  the  egg  was  laid. 

Only  a  single  larva  inhabits  a  kernel  of  wheat,  but  several 
will  often  be  found  in  that  of  corn.  Not  only  do  the  larvae  injure 
the  grain,  but  the  beetles  feed  upon  it,  and  then  hollow  out  a  shelter 
for  themselves  within  the  hull.  The  beetles  are  quite  long-lived, 
and  thus  do  considerable  damage.  The  egg-laying  period  is 
equally  long,  and  as  there  are  three  or  four  broods  in  the  North 
and  six  or  more  in  the  South,  it  has  been  estimated  that  the  prog- 
eny of  one  pair  would  amount  to  6000  insects  in  a  single  season. 

Grain-beetles 

Another  beetle  very  common  in  the  granary,  but  of  quite 
different  appearance,  is  the  Saw-toothed  Grain-beetle*  (Fig.  151). 


Fig.  151. — ^The  saw-toothed  grain  beetle  (Silvanus  surinamensis) :  a,  adult 
beetle;  b,  pupa;  c,  larva — all  enlarged;  ,  d,  antenna  of  larva — still  more 
enlarged;  d,  the  red  or  square-necked  grain  beetle  (Catkartus  gemellatus 
Duv.)     (After  Chittenden,  U.  S.  Dept.  Agr.) 

It  is  a  cosmopoHtan  pest  and  is  also  nearly  omnivorous.  The 
beetle  is  only  about  one-tenth  of  an  inch  long,  very  much  flattened, 
of  a  dark-brown  color,  and  may  be  easily  recognized  by  the  six  saw- 
like teeth  on  each  side  of  the  thorax.  The  larva  is  of  a  dirty- 
white  color,  and  quite  dissimilar  to  that  of  the  granary  weevil. 
*  Silvanus  surinamensis  Linn.     Family  Cucujidce. 


178         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Having  six  legs  to  carry  it  about,  it  is  not  satisfied  with  a  single 
seed,  but  runs  about  here  and  there,  nibbling  at  several.  When  full 
grown  the  larva  glues  together  several  grains  or  fragments  intoa  little 
case,  and  inside  of  this  transforms  to  the  pupa  and  then  to  the  beetle. 
In  early  spring  this  life  cycle  requires  from  six  to  ten  weeks,  but  in 
summer  it  is  reduced  to  about  twenty-five  days.     Thus  there  are 


^^^" 


Fig.  152. — The  Cadelle  (Tenehroides  mauritanicus) :  a,  adult  beetle  with 
greatly  enlarged  antenna  above;  b,  pupa;  c,  larva — all  enlarged.  (After 
Chittenden,  U.  S.  Dept.  Agr.) 

from  three  to  six  or  more  generations  during  a  season,  according 
to  the  latitude. 

The  Red  or  Square-necked  Grain-beetle*  is  about  the  same 
size  as  the  last  species,  but  is  of  a  reddish-brown  color,  and  the 
thorax  is  almost  square,  nearly  as  broad  as  the  abdomen,  and 
not  notched  on  the  sides.  It  breeds  in  corn  in  the  field  and  in 
the  granary,  first  destroying  the  germ,  so  that  it  is  especially 

*  Cathartus  gemellatus  Duv.     Family  TenehrionidoB. 


INSECTS  INJURIOUS  TO  STORED  GRAINS 


179 


injurious  to  seed-corn.  It  feeds  mostly  out  of  doors,  though 
sometimes  infesting  the  granary. 

The  Foreign  Grain-beetle*  is  of  much  the  same  general  ap- 
pearance, but  smaller  and  of  a  more  robust  appearance.  It 
feeds  upon  a  great  variety  of  stored  products  as  well  as  grain, 
but  rarely  becomes  troublesome. 

The  Cadellef  also  has  the  bad  habit  of  first  attacking  the 
embryo  or  germ  of  the  kernel,  and  going  from  one  kernel  to  another, 
thus  destroys  a  large  number  for  seed  purposes.  It  possesses, 
however,  the  good  trait  of  feeding  on  other  injurious  grain- 
insects.  The  beetle  is  oblong,  flat,  nearly  black,  and  about 
one-third  of  an  inch  long.  The  larva  is  of  a  whitish  color,  with  a 
brown  head,  the  thoracic  segments  are  marked  with  brown,  and 


Fig.  153. — The  Mediterranean  flour-moth  (Ephestia  kuehniella) :  a,  moth; 
6,  same  from  side,  resting;  c,  larva;  d,  pupa — enlarged;  e,  abdominal 
joint  of  larva — more  enlarged;  /,  larva,  dorsal  view.  (After  Chittenden, 
U.  S.  Dept.  Agr.) 

the  abdomen  terminates  in  two  dark  horny  processes.     It  is  a 
fleshy  grub,  nearly  three-fourths  of  an  inch  long  when  full  grown. 

Flour-  and  Meal-moths 

The  larvae  of  several  small  moths  sometimes  infest  grain 
in  store,  but  rarely  do  it  serious  damage,  preferring  the  softer 
flour,  meal  and  food-products. 

The  most  destructive  of  these  is  the  Mediterranean  Flour 
mothj    (Fig.    153).     This  insect  was  practically  unknown   until 

*  Cathartus  advena  Waltl. 

t  Tenebroides  mauritanicus  Linn.     Family  Trogositidas. 

X  Ephestia  kuehniella  Zell.  Family  Pijralididoe.  See  W.  G.  Johnson,  Ap- 
pendix 19th  Report  State  Entomologist  of  lUinois,  and  F.  L.  Washburn, 
Special  Report  of  the  State  Entomologist  of  Minnesota  on  the  Mediter- 
ranean flour-moth. 


180        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


1877,  but  during  recent  years  it  has  occasioned  the  loss  of  many 
thousands  of  dollars  to  mill-owners.  It  occurs  throughout 
Europe,  and  is  found  in  Mexico  and  Chili.  It  was  first  recognized 
in  America  in  1889,  and  has  since  done  an  increasing  amount 
of  damage  in  California,  in  New  York  and  Pennsylvania,  North 
Carolina,  Alabama,  New  Mexico,  and  Colorado,  and  has  become 
quite  generally  distributed.  "  The  caterpillars  form  cylindrical 
silken  tubes  in  which  they  feed,  and  it  is  in  great  part  their  habit 
of  web-spinning  that  renders  them  so  injurious  where  they  obtain 
a  foothold.  Upon  attaining  full  growth  the  caterpillar  leaves 
its  original  silken  domicile  and  forms  a  new  web,  which  becomes 


Fia.  154. — ^The  Indian  meal-moth  (Plodia  interpunctella) :  a,  moth;  b,  pupa; 
c,  caterpillar;  /,  same— dorsal  view,  somewhat  enlarged;  d,  head,  and 
e,  first  abdominal  segment  of  caterpillar — more  enlarged.  (After  Chit- 
tenden, U.  S.  Dept.  Agr.) 

a  cocoon  in  which  to  undergo  its  transformations  to  pupa  and 
imago.  It  is  while  searching  for  a  suitable  place  for  transforma- 
tion that  the  insect  is  most  troublesome.  The  infested  flour 
becomes  felted  together  and  lumpy,  the  machinery  becomes 
clogged,  necessitating  frequent  and  prolonged  stoppage,  and  result- 
ing in  a  short  time  in  the  loss  of  thousands  of  dollars  in  large 
establishments." 

The  life  cycle  of  this  insect  requires  ordinarily  about  two 
months,  but  may  be  completed  in  thirty-eight  days  under  the  most 
favorable  conditions.  The  adult  moth  measures  a  little  less  than 
an  inch  across  the  expanded  wings.  The  fore-wings  are  of  a  lead- 
gray  color,  with  transverse  black  markings,  while  the  hind- 
wings  are  dirty  whitish,  with  a  darker  border. 

The  Indian  Meal-moth*  (Fig.  154)  larvae  resemble  those  of 
the  grain-beetles  in  having  a  special  liking  for  the  embryo  of 

*  Plodia  interpwidella  Hbn.     Family  Pyralididce. 


INSECTS  INJURIOUS  TO  STORED  GRAINS 


181 


wheat-grains.  They  spin  a  fine  silken  web  as  they  go  from  seed 
to  seed,  to  which  they  become  attached,  and  to  which  is  added  a 
large  amount  of  excrement,  thus  spoiling  for  food  much  more 
grain  than  is  actually  injured. 

The  moth  has  a  wing-expanse  of  an  inch;  the  inner  third 
of  the  fore-wings  being  a  whitish-gray,  and  the  outer  portion 
reddish-brown,  with  a  coppery  lustre. 

The  Meal  Snout-moth*  (Fig.  155)  is  of  a  light  brown  color, 


Fig.  155. — ^The  meal  snout-moth  {Pyralis  farinalis):  a,  adult  moth;  b,  larva; 
c,  pupa  in  cocoon — twice  natural  size.  (After  Chittenden,  U.  S.  Dept. 
Agr.) 

the  thorax,  base,  and  tips  of  the  fore-wings  being  darker  brown. 
The  wings  expand  nearly  an  inch  and  are  otherwise  marked 
with  whitish  lines  as  shown  in  the  figure.  It  is  very  similar  to 
the  last-mentioned  species  in  its  habits,  constructing  long  tubes 
with  silk  and  particles  of  the  food  in  which  it  is  living.  The  life- 
history  is  completed  in  about  eight  weeks,  and  four  generations 
may  occur  in  a  year.  The  moisture  of  "heated"  grain  is  most 
favorable  for  the  development  of  this  pest,  and  it  need  not  be 
feared  if  grain  is  kept  in  a  clean,  dry  place. 

The  Pink  corn-wormf  has  recently  assumed  importance  in 
the  southern  states  as  an  enemy  of  stored  corn.  It  is  a  moth 
similar  in  shape  to  the  Anguomois  grain-moth,  but  smaller  and 
different  in  color.  Its  wing  expanse  is  less  than  one-half  inch 
and  its  color  is  chestnut-brown  with  whitish-yellow  markings. 
There  are  long  fringes  on  the  margins  of  both  pairs  of  wings. 
The  eggs  are  first  laid  on  corn  in  the  field,  usually  following  injury 
from  the  earworm  or  other  insect.  Later  generations  attack  corn  in 
the  crib.  The  larvae  are  small  pinkish  caterpillars.  They  feed  on 
grain  and  even  on  husks  and  cobs  and  spin  webs  wherever  they  go. 

*  Pyralis  farinalis  Linn.     Family  Pyralididoe. 
t  Batrachedra  rileyi  Wals.     Family  ElachistidoB. 


182       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Angoumois  Grain-moth  * 

By  far  the  worst  granary  pest  throughout  the  South  is  the 
"  fly-weevil,"  or  Angoumois  grain-moth. 

History. — This  insect  is  an  importation  from  Europe  and  receives 
its  name  from  the  fact  that  in  1760  it  "  was  found  to  swarm  in  all 
the  wheat-fields  and  granaries  of  Angoumois  and  of  the  neighbor- 
ing provinces  [of  France],  the  afflicted  inhabitants  being  thereby 
deprived  of  their  principal  staple,  and  threatened  with  famine 
and  pestilence  from  want  of  wholesome  bread."  The  insect 
was  first  noted  in  this  country  in  North  Carolina  in  1730,  and  in 
1796  was  so  abundant  as  to  extinguish  a  lighted  candle  when  a 
granary  was  entered  at  night.     It  is  essentially  a  southern  insect, 

being  very  injuri- 
ous to  stored  corn 
in  the  Gulf  States. 
Of  late  years  it 
seems  to  be  mov- 
ing steadily  north- 
ward, being  re- 
ported as  injurious 
in  central  Pennsyl- 
vania and  Ohio. 
Wheat,  corn,  oats, 
rye,  barley,  sor- 
ghum-s  e  e  d,  and 
even  cow-peas  are 
subject  to  injury. 
Life  History. — The  injury  is  not  done  by  the  moth,  as  might 
be  reasonably  supposed  from  the  fact  that  it  is  the  only  form  of 
the  insect  usually  seen,  but  is  done  by  the  small  caterpillars 
which  feed  within  the  grain,  where  they  may  be  found  during 
the  winter.  The  caterpillar  eats  to  the  surface  of  the  kernel, 
but  not  through  it,  thus  leaving  a  thin  lid  which  the  moth  can 
easily  push  aside  when  it  comes  out  in  the  spring,  and  then  covers 
itself  with  a  fine  silken  web.  At  this  time  the  caterpillar  is 
usually  fully  grown  and  is  about  one-fifth  of  an  inch  long,  of  a  white 
color,  with  the  head  yellowish  and  harder,  and  having  six  jointed 

*  Sitrotoga  cerealella  Oliv.     Family  Gelechiidoe. 

See  J.  L.  King,  Circular  No.  1,  Pennsylvania  Dept.  Agr. 


Fig.  156. — The  Angoumois  grain-moth  (Sitotroga  cereal- 
ella): a,  eggs;  h,  larva  at  work;  c,  larva,  side  view; 
d,  pupa;  e,  moth;  f,  same,  side  view.  (After  Chitten- 
den, U.  S.  Dept.  Agr.) 


INSECTS  INJURIOUS  TO  STORED  GRAINS 


183 


^i^i 


_£l^ 


legs  in  front,  a  series  of  four  pairs  of  fleshy  pro-legs  along  the 
middle,  and  another  pair  of  soft  legs  at 
the  end  of  the  body.  With  warm  spring 
weather  the  caterpillar  changes  to  a  pupa, 
and  about  the  time  that  the  wheat  comes 
into  head  the  adult  moth  emerges.  As  soon 
as  it  emerges,  whether  outdoors  or  in  a  barn, 
the  moth  at  once  flies  to  the  grain-field, 
where  the  eggs  are  deposited.  The  exact 
time  at  which  the  moths  emerge  varies,  but 
occurs  some  time  late  in  May  or  in  June. 
The  moths  quite  closely  resemble  the 
clothes-moth  often  found  flying  about 
houses.  The  wings  are  quite  narrow,  and 
when  expanded  measure  about  one-half  an 
inch  from  tip  to  tip,  being  of  a  yellowish  or 
buff  color,  marked  with  black.  The  eggs 
are  laid  in  the  longitudinal  channel  on  the 
side  of  the  grain.  Each  female  lays  from 
sixty  to  ninety  eggs  in  lots  of  about  twenty 
each,  one  lot  thus  being  about  enough  to  in- 
fest the  kernels  of  a  head.  The  eggs  hatch 
in  from  four  to  seven  days.  The  young  cat- 
erpillars are  at  first  very  active  and  soon 
find  tender  places  and  bore  into  the 
kernels,  leaving  almost  invisible  openings. 
These  caterpillars  become  full  grown  in 
about  three  weeks,  just  about  the  time  the 
grain  is  mature.  About  harvest-time  the 
second  brood  of  moths  appears.  These  lay 
their  eggs  during  July,  depositing  them  on 
the  ripe  heads  if  the  harvest  be  a  little  de- 
layed, but  on  the  wheat  in  stack  if  harvest 
is  prompt.  Usually  the  caterpillars  hatch- 
ing from  these  eggs  become  full  grown  and 
remain  in  the  grain  over  winter,  but  in 
warm  seasons,  especially  if  warm  in  Sept- 
ember or  when  the  pest  is  unusually  abun- 
dant, a  third  brood  of  moths  appears 
early  in  September.      These   lay   another 


^1 


•  ©) 


n 


Fig.  157. — Ear  of  pop- 
corn, showing  work  of 
Angoumois  grain- 
moth.     (After  Riley.) 


184  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

batch  of  eggs  about  the  middle  of  September,  depositing  them  up- 
on the  open  ends  of  grain  in  stack  or  mow,  which  thus  becomes 
more  infested  than  that  in  the  centre.  In  grain  stacked  outside,  the 
caterpillars  of  this  brood  become  full  grown  slowly  and  remain  in 
the  grain  over  winter,  but  if  in  the  barn  they  grow  faster  and  a 
fourth  brood  of  moths  appears  about  the  middle  of  October,  the 
moths  being  noticed  in  threshing.  The  insects  continue  to  breed 
within  doors  all  winter  as  long  as  any  grain  remains,  though  they 
become  sluggish  and  cease  feeding  during  cold  weather.  The 
number  of  broods  is  entirely  dependent  upon  the  latitude  and 
weather  conditions;  in  the  South,  where  they  can  breed  continu- 
ously, there  being  as  many  as  eight  in  a  year. 

Corn  is  frequently  attacked,  but  not  until  it  is  ripe  and  husked, 
and  then  but  rarely  when  husked  in  October  and  November  and 
stored  outdoors  in  slatted  cribs.  Seed-corn  stored  in  barns,  and 
in  the  South  in  almost  any  situation,  is  often  badly  injured. 

Aside  from  the  loss  in  weight,  grain  when  badly  infested 
becomes  unfit  for  milling  purposes,  and  will  even  be  refused  by 
cattle  and  horses,  which  should  not  be  urged  to  eat  it,  though 
hogs  and  fowls  will  readily  consume  it. 

Remedies. — Dr.  J.  B.  Smith,  in  an  interesting  bulletin  upon 
this  pest,  to  which  we  are  indebted  for  much  of  the  above,  advises 
as  follows:  ''Thresh  as  soon  after  harvest  as  possible,  and  bulk  in 
tight  bins  or  in  good  sacks.  [By  "tight  bins"  are  meant  those 
which  will  not  permit  the  entrance  or  exit  of  the  moths.]  If  the 
grain  is  dry  when  harvested,  it  may  be  threshed  at  once;  if  not,  as 
soon  as  it  is  in  good  condition.  If  the  sacked  grain  is  infested, 
there  will  not  be  wormy  kernels  sufficient  to  heat  the  grain.  The 
moths  cannot  make  their  way  out  and  are  stifled.  Nothing  can 
come  in  from  outside  and  the  grain  remains  safe.  The  threshing 
itself  kills  many  of  the  insects  and  jars  and  rubs  off  many  of  the 
eggs.  If  binned,  the  bins  should  be  tight  and  the  grain  should  be 
tested  occasionally  for  any  appreciable  heating.  If  it  heats  per- 
ceptibly, it  indicates  considerable  infestation,  and  it  should  be 
treated  with  carbon  bisulfide  at  once,  used  at  the  rate  of  one 
drachm  per  cubic  foot,  or  1  pound  for  250  cubic  feet  bin-space." 
Recent  investigations  have  shown  that  more  bisulfide  will  often 
be  necessary. 

Those  having  wheat  unthreshed,  whether  in  stack  or  mow, 
should  thresh  at  once,  and  treat  as  above  directed,  except  that  if 


INSECTS  INJURIOUS  TO  STORED  GRAINS  185 

much  of  it  is  noticed  to  be  worm}^,  it  should  be  treated  with  carbon 
bisulfide  at  once,  as  soon  as  threshed,  which  if  done  thoroughly 
will  prevent  any  further  infestation  that  year. 

Barns  and  storehouses  should  be  cleaned  up  and  freed  from  all 
loose  and  scattered  grain — chickens  will  help  in  this — before  April 
1st,  so  that  no  moths  will  be  allowed  to  develop  and  infest  the 
grain  in  the  field.  Places  where  grain  has  been  in  stock  the  pre- 
vious season  should  be  cleaned  up  by  the  aid  of  chickens.  Thus  if 
there  is  any  probability  of  grain  being  infested,  it  should  be  kept 
tightly  covered  in  the  spring  so  as  not  to  permit  the  spread  of  the 
moths  to  the  fields. 

Prevention  of  "  Weevil  " 

Undoubtedly  grain-insects  can  usually  be  more  successfully 
combated  by  a  proper  housing  of  the  grain.  No  matter  how  often 
the  insects  are  destroyed  in  a  granary,  if  the  remainder  of  the  barn 
is  full  of  dust,  sweepings,  and  refuse,  as  it  generally  is,  on  which 
the  beetles  can  feed  and  in  which  they  will  breed,  and  if  the  gran- 
ary is  not  absolutely  tight,  as  soon  as  the  gas  passes  off  the  insects 
from  the  barn  will  again  enter  the  granary,  and  soon  it  will  be  as 
badly  infested  as  ever. 

Cleanliness. — "  Cleanliness  will  accomplish  much  toward  the 
prevention  of  injury  from  these  pests,  the  cause  of  a  great  propor- 
tion of  injuries  in  granaries,  mills,  elevators,  and  other  structures 
where  grain  and  feed  are  stored  being  directly  traceable  to  a  dis- 
regard of  neatness.  Dust,  dirt,  rubbish,  and  refuse  material  con- 
taining sweepings  of  grain,  flour,  and  meal  are  too  frequently  per- 
mitted to  accumulate  and  serve  as  breeding-places  for  a  multitude 
of  injurious  insects. 

"  The  floors  or  corners  and  walls  of  the  barn  or  storehouse 
should  be  frequently  swept,  and  all  material  that  has  no  conruner- 
cial  value  burned." 

The  Granary. — "  The  ideal  farmer's  granary,  from  the  stand- 
point of  insect  ravages,  should  be  built  at  some  distance  from 
other  buildings,  and  the  rooms  constructed  of  matched  floorings 
so  as  to  be  as  near  vermin-proof  as  possible.  The  doors  should  fit 
tightly,  closmg  upon  a  rabbet,  which  may  be  covered  with  felt  or 
packing,  and  the  windows  covered  with  frames  of  wire  gauze  to  pre- 
vent the  passage  of  insects.  The  floor,  walls,  and  ceilings  should 
be  smooth,  so  as  not  to  afford  any  lurking-places  for  the  insects, 


186         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

and  it  would  be  well  to  have  them  oiled,  painted,  or  whitewashed 
for  further  security.  A  coating  of  coal  tar  has  been  strongly 
recommended  for  the  latter  purpose." 

"  The  value  of  a  cool  place  as  a  repository  of  grain  has  been 
known  of  old,  and  a  building  in  which  any  artificial  heat  is  em- 
ployed is  undesirable  for  grain  storage.  The  *  heating '  and  fer- 
mentation of  grain,  as  is  well  known,  is  productive  of '  weevil, '  and 
this  should  be  prevented  by  avoiding  moisture  and  by  ventilation. 

The  storage  of  grain  in  large  hulk  is  to  be  commended,  as  the 
surface  layers  only  are  exposed  to  infestation.  This  practice  is 
particularly  valuable  against  the  moths,  which  do  not  penetrate 
far  beneath  the  surface.  Frequent  agitation  of  the  grain  is  also 
destructive  to  the  moths,  as  they  are  unable  to  extricate  them- 
selves from  a  large  mass,  and  perish  in  the  attempt.  The  true 
granary-weevils  (small  dark-brown  beetles  with  long  curved 
snouts,  similar  to  the  pea- weevil),  however,  penetrate  more 
deeply,  and  although  bulking  is  of  value  against  them,  it  is  not 
advisable  to  stir  the  grain,  as  it  merely  distributes  them  more 
thoroughly  through  the  mass." — Chittenden 

Recent  observations  and  experiments*  have  shown  that  in 
the  southern  states,  at  least,  injury  to  corn  from  the  forms  of  weevil 
which  infest  the  ears  in  the  field,  as  well  as  some  corn  earworm 
injury,  may  be  largely  prevented  by  planting  varieties  of  corn 
which  produce  ears  covered  with  husks  which  extend  beyond  the 
tip  of  the  ears  and  form  a  close  sheath  for  the  ear,  leaving  no 
opening  for  the  entrance  of  the  weevil.  Since  there  is  more  hkeli- 
hood  of  infestation  from  several  species  of  weevils  on  corn  in  the 
field  in  the  South,  the  use  of  such  varieties  would  seem  to  be  good 
practice  for  that  region. 

Destruction  of  "  Weevil  " 

^Carbon  Bisulfide. — "  The  simplest,  most  effective,  and  most 
inexpensive  remedy  for  all  insects  that  affect  stored  grain  and 
other  stored  products  is  the  bisulfide  of  carbon,  a  colorless  liquid, 
with  a  strong  disagreeable  odor,  which,  however,  soon  passes 
away."  At  ordinary  temperatures  it  vaporizes  rapidly,  forming  a 
heavy  gas,  which  is  highly  inflammable  and  a  powerful  poison. 

*  E.  A.  Back,  Farmers'  Bulletin  1029,  U.  S.  Dept.  of  Agr. 
t  See  W.  E.  Hinds,  Farmers'  Bulletin  799,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  STORED  GRAINS  187 

Application. — It  may  be  applied  direct!}'  to  the  infested  grain 
or  seed  without  injury  to  its  edibleness  or  viability  by  spraying 
with  an  ordinary  watering-can  having  a  fine  rose  nozzle.  In 
moderatel}^  tight  bins  it  is  more  effective,  however,  as  it  evaporates 
more  slowly  and  diffuses  more  evenly,  if  placed  in  shallow  dishes 
or  pans,  or  on  bits  of  cloth  or  cotton  waste  distributed  about  on 
the  surface  of  the  grain  or  infested  material.  The  liquid  volatil- 
izes rapidly,  and,  being  heavier  than  air,  descends  and  permeates 
the  mass  of  grain,  killing  all  insects  and  other  vermin  present. 
The  bin  should  then  be  covered  with  boards,  canvas,  or  blankets, 
and  allowed  to  remain  at  least  twenty-four  hours.  If  to  be  used 
for  seed,  it  should  not  be  left  for  over  thirty-six  hours;  but  if  not, 
leave  it  fortj^-eight  hours,  which  Avill  do  it  no  injury  for  food 
After  treating  keep  the  grain  covered  to  prevent  reinfestation. 

Amount  to  Use. — It  was  formerly  recommended  that  the  bisul- 
fide be  applied  at  the  rate  of  1  to  3  pounds  to  100  bushels  of  grain 
or  1000  cubic  feet  of  open  space.  Recent  experiments,  however, 
have  shown  the  total  inadequacy  of  this  dosage.  Experiments 
made  by  Hinds  and  Hunter*  show  that  the  effectiveness  of  the 
gas  is  in  direct  proportion  to  the  temperature.  Below  60°  F.  the 
fumigation  is  ineffective  and  inadvisable.  A  dosage  which  will 
kill  practically  all  the  weevil  at  67°  to  70°  will  kill  but  60  to  70  per 
cent  at  60°  to  65°.  They  recommend  the  use  of  5  pounds  per 
1000  cubic  feet  where  the  room  or  bin  is  quite  tight  and  the  tem- 
perature is  70°  or  above.  For  open  rooms  and  lower  tempera- 
tures, the  dosage  must  be  largely  increased  and  may  not  be  profit- 
able. The  above  estimates  are  based  upon  the  grain  being  in  a 
cubical  shape;  if  it  is  spread  out  shallow,  more  bisulfide  will  be 
necessary. 

Caution. — "  Certain  precautions  should  always  be  observed. 
The  vapor  of  carbon  bisulfide  is  deadly  to  all  forms  of  animal 
life  if  inhaled  in  suffi^cient  quantity,  but  there  is  no  danger  in 
inhaling  a  small  amount.  The  vapor  is  highly  inflammable, 
but  with  proper  care  that  no  fire  of  any  kind,  as,  for  example, 
a  lighted  cigar,  lantern,  or  light  of  any  kind,  be  brought  into 
the  vicinity  vmtil  the  fimies  have  entii'el}^  passed  away,  no  trouble 
will  be  experienced." 

Hydrocyanic  Acid  Gas. — Mills  and  storehouses  which  needed 

*  Hinds  and  Hunter,  Journal  of  Economic  Entomologv,  Vol.  Ill,  p.  47: 
R.  I.  Smith,  Bulletin  203,  N.  C.  Agr.  Exp.  Sta. 


188        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

treatment  were  formerly  fumigated  with  carbon  bisulfide,  which 
is  still  employed  to  a  considerable  extent,  but  this  has  been 
largely  replaced  by  fumigation  with  hydrocyanic  acid  gas,  which 
obviates  the  risk  from  fire.  Directions  for  the  use  of  this  gas 
should  be  obtained  from  the  entomologist  of  the  State  Experiment 
Station  or  from  the  Bureau  of  Entomology  of  the  U.  S.  Depart- 
ment of  Agriculture. 

Sulfur  Fumes. — Professor  R.  I.  Smith  (1.  c.)  has  made  experi- 
ments with  sulfur  dioxid,  produced  by  burning  sulfur  slightly  wet 
with  alcohol,  and  finds  that  it  will  effectively  kill  grain  insects 
but  injures  the  germinating  power  of  the  grain.  "  It  was  found  that 
the  fumes  produced  by  burning  2|  pounds  of  sulfur  either  in  a 
moist  or  dry  atmosphere  of  1000  cubic  feet  space,  for  twenty 
hours,  would  kill  all  exposed  adult  insects  and  practically  all  the 
young  stages  in  the  grain,  but  that  this  also  destroyed  its  germinat- 
ing power.  .  .  While  this  treatment  cannot  be  recommended 
for  general  fumigation,  there  is  no  doubt  of  its  being  the  easiest 
and  cheapest  method  of  fumigating  corn  cribs,  granaries  and 
similar  places  whenever  they  are  being  cleaned  out  and  freed 
of  insects  in  preparation  for  the  reception  of  more  grain." 

Heat. — The  heating  of  grain  was  one  of  the  earliest  means 
known  of  combating  grain  insects,  but  has  been  little  used  in  this 
country.  Recently,  however,  Prof,  Geo.  A.  Dean  of  the  Kansas 
Agricultural  Experiment  Station,*  has  shown  that  by  super- 
heating mills  they  may  be  rid  of  insect  pests  much  more  quickly 
and  cheaply  than  by  fumigation,  and  with  no  risk  from  fire,  or 
from  cyanide  poisoning.  His  experiments  show  that  if  the 
temperature  surrounding  an  insect  be  maintained  above  120°  F., 
with  a  normal  amount  of  moisture,  that  in  a  very  few  minutes  it 
will  be  killed.  This  has  become  one  of  the  most  popular  methods 
of  cleaning  mills  and  may  be  used  for  small  quantities  of  grain 
where  there  are  facilities  for  heating  it  or  placing  it  in  a  super- 
heated room,  but  probably  carbon  bisulfide  fumigation  will  be 
found  more  practicable  for  small  amounts. 

*  Geo.  A.  Dean,  Journal  of  Economic  Entomology,  Vol.  IV,  p.  142  and 
Bulletin  189,  Kansas  Agr.  Expt.  Station. 


CHAPTER  XI 


INSECTS  INJURIOUS  TO  CLOVER  AND  ALFALFA.* 
The  Clover  Root-borer  j 

The  Clover  Root-borer  is  practically  the  only  insect  pest 
which  seriously  injures  clover  roots.  It  has  long  been  known  as 
a  clover  pest  in  Europe,  but  was  first  noticed  in  this  country  in 
western  New  York  in  1876,  whence  it  has  spread  southward  to 
West  Virginia  and  westward  to  Illinois  and  southern  Michigan, 
and  has  also  been  injurious  in  Oregon. 

Life  History. — During  the  winter  the  beetles  may  be  found 
hibernating  in  their  burrows  in  infested  clover  roots.  They  are 
not    readily    distinguishable,    for   they   are    scarcely   one-eightb 


Fig.  158. — ^The  clover  root-borer  {Hylastinus  obscurus):  a,  adult,  natural 
size  at  right;  b,  larva  or  grub,  c,  pupa — much  enlarged.  (After  Webster, 
U.  S.  Dept.  Agr.) 

inch  long,  and  are  of  a  reddish-brown  color  much  Hke  that  of  the 

burrow.     With  the  warmer  weather  of  spring  they  commence 

*  See  The  Insect  Pests  of  Clover  and  Alfalfa,  J.  W.  Folsom,  25th  Report 
of  the  State  Entomologist  of  Illinois,  pp.  41-124,  and  Bulletin  134,  Illinois 
Agr.  Expt.  Station. 

t  Hylastiniis  obscurus  Marsham.     Family  Scolytidoe. 

189 


190 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


burrowing  and  feeding  in  the  roots,  and  during  late  May  and 
early  June  the  females  deposit  their  eggs  along  the  sides  of  the 
tunnels.  "The  female  gouges  out  a  shallow  cavity,  more  often  in 
the  crown  of  the  plant,  sometimes  at  the  sides  of  the  root  even 
2  or  3  inches  below  the  crown,  and  in  this 
places  singly,  but  not  far  separated,  about 
a  half  dozen  pale  whitish,  elliptical,  very 
minute  eggs.  These  hatch  in  about  a 
week,  and  the  larvae  for  a  time  feed  in 
the  excavation  made  by  the  mother, 
)ut  soon  burrow  downward  into  the  root, 
and  before  the  1st  of  August,  the  majority 
of  them  have  become  full-grown,  and 
passed  into  the  pupal  stage.  By  October 
nearly  all  have  become  fully  developed 
beetles,  but  they  make  no  attempt  to 
leave  the  plant  until  the  following  spring." 
The  spread  of  the  insect  occurs  very  large- 
ly in  the  spring  when  the  beetles  fly  from 
field  to  field,  seeking  uninfested  plants  in 
which  to  perpetuate  their  kind. 

It  has  been  observed  that  alsike  clover  is 
not  so  badly  injured  as  the  mammoth  and 
common  red  clover,  on  account  of  the 
fibrous  roots  and  the  tendency  of  its  tap- 
root to  divide.  In  Europe  alfalfa  is  injured, 
but  little  injury  has  yet  been  reported  to 
that  crop  in  this  country,  as  yet. 

"While  an  infested  clover  plant  sooner 
or  later  succumbs  to  an  attack  by  this  in- 
sect, life  may  be  lengthened  or  shortened  by 
meteorological  conditions.  Thus,  if  the 
spring  or  early  summer  is  very  dry,  the 
plants  begin  to  dry  in  patches  late  in  June, 
as  soon  as  the  hay  crop  is  removed;  but 
if  there  is  much  rain  during  this  period,  the  weakened  plants  may 
continue  to  live  until  winter,  dying  out  before  spring.  In  either 
case  the  farmer  is  likely  to  be  misled  and  attribute  the  loss 
to  the  weather."     Clover  is  practically  exempt  from  attack  the 


Fig.  159. — Clover  root 
showing  work  of  clover 
root-borer.  Slightly  en- 
larged. (After  Web- 
ster,) U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  CLOVER  AND  ALFALFA 


191 


first  year  as  the  roots  are  not  large  enough  to  accommodate  the 
insects,  and  it  is  not  until  the  second  year  that  the  plants  are 
destroyed. 

Control. — The    only  effective  means  of    control  suggested  is 
summer  fallowing  as  soon  as  the  hay  crop  has  been  removed. 


Fig.  160. — Present  known  distribution  in  the  United  States  of  the  clover-root 
curculio.     (After  F.  M.  Webster,  L.  C.) 

The  field  should  then  be  plowed  up  at  once,  before  the  larvsB 
have  transformed  to  pupse,  so  that  the  hot  sun,  and  dry  winds, 


Fig.  16L — Stages  of  the  clover-root  curculio,      (After  Webster,  L.  C,  from 
Wildermuth):  a,  adult;  b,  larva;  c,  pupa. 

will  dry  out  the  roots  of  the  clover  and  thus  starve  the  larvae, 
thereby  preventing  their  developing  and  migrating  to  other 
fields.     Clover  fields  should  not  be  allowed  to  stand  over  two 


192  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

years  in  infested  localities.  No  injury  seems  to  be  done  in  pas- 
tures. A  system  of  rotation  in  which  the  crop  is  mowed  for  hay 
and  seed  the  first  year,  and  pastured  and  then  broken  up  the 
second  year,  should  keep  the  pest  under  control. 

An  insect  very  similar  in  life-history  and  nature  of  injury  is 
the  Clover-root  Curculio.*  This  insect  is  also  a  snout  beetle 
but  belongs  to  a  different  family.  In  spite  of  this,  the  adults 
and  larvse  will  both  probably  be  confused  by  the  ordinary 
observer.     The  curculio  has  been  observed  working  on  alfalfa.f 

The  Clover  Leaf-weevil  X 

The  clover  leaf-weevil  is  a  stout,  oval  beetle,  about  one-third 
inch  long,  with  a  long,  thick  snout.  It  is  of  a  brownish  color, 
with  several  narrow  gray  lines  above  and  broad  gray  stripes 
on  each  side,  and  with  twenty  rows  of  small,  deep  punctures 
on  the  wing-covers.  It  also  is  a  native  of  Europe  and  made  its 
first  appearance  in  the  same  section  of  western  New  York  as  the 
last  species,  about  1881.  Since  then  it  has  spread  eastward  to 
Rhode  Island  and  Vermont,  southward  to  North  Carolina  and 
West  Virginia  and  westward  to  Wisconsin  and  Illinois.  Every 
few  years  the  weevils  and  their  larvse  destroy  much  of  the  foliage 
in  restricted  localities,  but  rarely  are  they  very  injurious  the  next 
season.  Red  clover,  alfalfa,  and  white  clover  are  preferred  in  the 
order  named;  in  Illinois  the  mammoth  and  alsike  are  also  eaten. 

Life  Hitsory. — In  early  fall  the  female  beetles  lay  their  eggs 
in  crevices  among  the  stems  near  the  base  of  the  plant,  which 
hatch  in  from  three  to  six  weeks.  The  young  larvse  which  hatch 
from  them  are  without  legs,  but  manage  to  climb  by  means  of 
the  prominent  tubercles  on  the  lower  surface  of  the  body.  They 
are  light  yellowish-green,  becoming  deeper  green  as  they  grow 
older,  the  head  is  brown,  and  down  the  middle  of  the  back  is 
a  white  or  pale  yellow  stripe  bordered  with  reddish.  The  larvse 
become  partially  grown  before  winter  sets  in,  when  they  hiber- 
nate in  rubbish  or  just  under  the  soil  until  spring,  when  they 
continue  to  feed  upon  the  foliage  and  become  full-grown  in  May 
and   early  June.     They  feed  mostly  at  night  and  are  hardly 

*  Sitones  hispidulis  Fabricius.     Family  Curculionida. 

t  See  F.  M.  Webster,  Farmers'  Bulletin  649,  U.  S.  Dept.  of  Agr. 

X  Phytonomus  punctatus  Fab.     Family  Curculionidoe. 


INSECTS  INJURIOUS  TO  CLOVER  AND  ALFALFA  193 

noticeable  in  the  day,  when  they  he  protected  around  the  base 
of  the  plant,  lying  curled  up  head  to  tail.  The  injury  to  the 
foliage  is  quite  characteristic,  the  edges  of  the  leaves  being  eaten 
in  a  regular  manner  as  shown  in  Fig.  162.  When  full  grown  the 
larva  buries  itself  just  under  the  surface  of  the  soil  and  makes 
an  oval  cell,  in  which  it  spins  a  delicate  cocoon  consisting  of  a 
coarse  network  of  pale  yellow  threads,  which  later  turn  brown, 


Fig.  162. — Clover  leaf -weevil  (Phytonotnus  pundatus  Fabr.) :  a,  egg  magnified 
and  natural  size;  bbb  b,  larvi3e;  c,  recently  hatched  larva;  d,  head  of 
larva;  e,  jaws  of  the  same;  /,  cocoon;  g,  same  magnified  to  show  the 
meshes;  h,  pupa;  i,  weevil,  natural  size;  j,  the  same  magnified;  k,  top 
view  of  the  beetle;  I,  tarsus  and  claws  of  the  beetle;  m,  antenna  of  the 
beetle.     (After  Riley.) 

as  shown  in  Fig.  162.  Occasionally  the  cocoon  is  made  on  the 
surface  or  among  the  bases  of  the  stems.  In  this  the  pupal 
stage  is  passed,  lasting  two  or  three  weeks;  the  beetles  being 
most  common  in  July  and  August.  The  damage  which  the 
beetles  do  to  the  second  crop  of  clover  is  fully  equal  that  done 
by  the  larvse  to  the  first,  and  is  more  apparent  because  the  soil 
is  then  dry  and  the  plant  grows  more  slowly. 


194      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

That  this  insect  has  not  become  a  more  serious  pest  is  due  to 
the  fact  that  as  often  as  it  becomes  excessively  abundant  the 
larvse  are  ahnost  completely  destroyed  by  a  fungous  disease.* 
When  affected  by  this  disease  the  larvse  climb  to  the  top  of  a 
blade  of  grass,  curl  tightly  around  the  tip,  and  soon  die,  first 
becoming  covered  with  a  white  mold  and  then  turning  to  a  jelly- 
like mass.  The  spores  of  the  fungus  become  scattered  to  healthy 
individuals,  which  soon  succumb,  so  that  before  long  nearly  all. 
are  destroyed,  and  rarely  do  enough  survive  to  cause  trouble 
the  next  year. 

Frequent  reports  are  received  of  poisoning  of  cattle  which 
have  fed  on  clover  having  numbers  of  the  larvae  which  have  died 
from  this  fungus.  Accounts  vary,  some  reporting  serious  sick- 
ness and  even  death  as  the  result  and  others,  probably  more 
authentic,  reporting  merely  temporary  sickness.  In  any  case, 
it  will  be  well  to  keep  cattle  from  the  infested  plants. 

Control. — On  account  of  this  disease  repeated  injury  has  been 
so  rare  that  no  means  of  artificial  control  has  been  necessary. 
"The  necessity  for  the  employment  of  any  remedy  does  not 
appear  until  the  clover  is  well  on  in  its  second  year's  growth," 
says  Dr.  Folsom  (I.e.).  "If  damage  is  anticipated,  however,  it 
would  seem  advisable  to  pasture  the  clover  lightly  or  to  clip 
back  in  the  spring;  this  does  not  hurt  the  clover,  is  highly  desir- 
able as  a  means  of  forestalling  the  attacks  of  some  other  clover 
pests  (see  page  201),  and  might  check  the  larvse  of  the  leaf-weevil 
somewhat,  though  it  is  possible  that  they  would  subsist  on  the 
cut  stems  until  the  new  growth  started;  and  in  cold  weather  they 
can  live  a  long  time  without  any  food.  After  the  second  season 
red  clover  should  be  plowed  under  to  get  rid  of  this  pest,  as  well 
as  for  other  agricultural  reasons." 

The  Alfalfa  Weevil  f 

In  recent  years  a  first  cousin  of  the  last  species  has  been 
introduced  into  Utah,  where  it  has  become  firmly  estabfished 
and  promises  to  become  the  most  serious  obstacle  to  alfalfa  culture. 
The  alfalfa  weevil  is  a  native  of  Europe,  western  Asia,  and  northern 

*  Empusa  sphceroperma  Fres. 

t  Phytonomus  posticus  Gyll.  Family  Curculionidce.  See  E.  G.  Titus, 
Bulletin  110  and  Circular  10,  Utah  Agr.  Exp.  Sta.,  and  F.  M.  Webster,  Circu- 
lar 137,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  CLOVER  AND  ALFALFA 


195 


Africa,  where  it  is  common  but  never  very  seriously  injurious.  It 
was  first  noticed  in  America  near  Salt  Lake  City,  Utah,  in  1904,  and 
has  been  increasing  and  spreading  until  it  now  occupies  an  area  of 
fully  100  square  miles  around  Salt  Lake  City.  The  beetles  are  from 
one-eighth  to  three-sixteenth  inch  long,  dark  brown,  marked  with 
black  and  gray  hairs  which  gives  them  a  mottled  appearance  as 
shown  in  Fig.  165.     These  hairs  or  scales  are  gradually  rubbed 


Fig.  163.— Chart  showing  the  life  history  df  the  Alfalfa  Weevil.      (From  H.  R. 
Hagan,  UtahAgr.  Expt.  Sta.  Circular  31. 

off,  SO  that  in  spring  many  individuals  are  entirely  black  with 
small  grayish  spots. 

Life  History. — The  beetles  seek  shelter  for  hibernation  before 
frost  in  the  autumn,  either  in  the  crowns  of  the  alfalfa  plants, 
or  under  thick  grass,  weeds,  rubbish;  leaves,  or  in  hay  or  straw 
stacks.  Often  they  winter  in  barns  where  the  hay  is  stored,  the 
floors  of  which  are  often  found  covered  with  the  beetles  in 
winter  and  spring.  It  is  estimated  that  fully  80  per  cent  of  the 
weevils  survive  the  winter  in  Utah.  In  the  spring  the  beetles 
emerge  and  attack  the  young  alfalfa  plants  as  soon  as  there  is 
sufficient  food  for  them,  usually  late  in  March.  The  females 
commence  laying  eggs  in  early  April  and  continue  oviposition 
until  early  July.     In  early  spring  while  the  plants  are  small  the 


196       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


females  often  push  their  eggs  down  between  the  leaves,  but  the 
usual  method  is  to  insert  them  in  punctures  made  in  the  stem. 

This  puncturing  of  the 
young  stems  often  re- 
sults in  considerable 
damage  in  early  spring. 
A  single  alfalfa  plant 
which  had  escaped  from 
cultivation  was  found 
to  contain  127  of  these 
punctures,  and  as  each 
puncture  contains  ten 
or  fifteen  eggs,  this  plant 
probably  bore  some 
1200  eggs,  although  it 
was  exceptional. 

The  eggs  hatch  in 
about  ten  days  and 
the  small  white  larvae 
make  their  way  to  the 
leaves  in  which  they 
eat  small  holes.  They 
soon  turn  a  decidedly  green  color,  and  when  full  grown  are  about 
one-half  inch  long  with  a  white  stripe  down  the  middle  of  the  back 


Fig.  164. — The  alfalfa  weevil,  adults,  clustering 
on  and  attacking  sprig  of  alfalfa — natural  size . 
(After  Webster,  U.  S.  Dept.  Agr.) 


Fig.  165. — The  alfalfa  weevil  {Phytonomus  posticus):  a,  eggs;  b,  cocoon; 
c,  larva;  d,  pupa;  e,  adult— all  much  enlarged.  (After  Webster,  U.  S. 
Dept.  Agr.) 


INSECTS  INJURIOUS  TO  CLOVER  AND  ALFALFA        197 

and  somewhat  curved  as  shown  in  Fig.  165.  They  attack  the 
young  leaves  and  crown  so  that  a  badly  infested  field  will  not  get 
over  six  inches  high;  too  short  to  mow.  .  The  larvae  are  most 
abundant  in  May  and  decrease  through  June.  When  full  grown 
the  larvae  crawl  or  drop  to  the  ground  and  spin  their  cocoons 
in  the  dead  leaves  or  rubbish.  The  cocoon  is  globular  and  com- 
posed of  a  network  of  rather  coarse  white  threads,  Fig.  165. 
In  it  the  larva  transforms  to  a  pupa,  which  stage  lasts  from 
one  to  two  weeks,  when  the  adult  beetle  emerges. 

From  early  to  midsummer  the  beetles  become  more  and  more 
abundant,  and  not  only  feed  on  the  fresh  growth,  but  attack  the 
bark  of  the  stems  so  that  where  excessively  abundant  they  totally 
destroy  the  second  crop. 

"The  entire  hfe  of  the  insect,  from  the  deposition  of  the  egg 
to  the  emergence  of  the  adult,  may  be  anywhere  from  forty  to 
seventy  days,  while  the  beetle  itself  may  live,  including  the  winter, 
from  ten  to  fourteen  months." — Webster. 

Inasmuch  as  literally  millions  of  the  beetles  have  been  gath- 
ered by  machines  from  a  single  acre,  and  as  the  beetles  have  been 
found  in  considerable  numbers  on  freight  and  passenger  trains, 
it  is  highly  probable  that  the  pest  will  be  spread  by  the  several 
trunk-lines  of  railroad  which  pass  through  the  infested  region,  as 
in  many  places  alfalfa  has  escaped  from  fields  and  grows  as  a 
weed  along  the  railway  tracks.  It  is,  therefore,  highly  important 
that  alfalfa  growers  be  on  their  guard  against  this  pest  and  take 
prompt  measures  for  its  destruction  wherever  it  may  gain  a 
foothold.  The  weevils  also  spread  rapidly  by  flying  in  spring 
and  summer,  which  migration  is  aided  by  the  winds.  They  may 
also  be  spread  in  articles  shipped  from  an  infested  region  and 
on  wagons  or  automobiles. 

Control. — The  methods  of  control  have  not,  as  yet,  been 
satisfactorily  determined,  though  the  entomologist  of  the  Utah 
Agricultural  Experiment  Station,  E.  G.  Titus,  from  whose  report 
the  following  summary  is  taken,  has  made  extensive  experiments 
with  various  methods. 

Old  alfalfa  fields  are  always  worst  injured,  and  fields  should 
not  be  left  down  in  alfalfa  over  about  seven  years.  Thorough 
disking  in  the  early  spring  has  proved  to  be  one  of  the  essential 
factors  in  securing  a  good  crop,  as  it  increases  the  stand  and 


198       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

stimulates  a  quick  growth  which  enables  the  plants  better  to 
withstand  the  weevil  injury.  The  use  of  a  brush  drag  with  which 
a  spike-tooth  harrow  is  combined  has  been  found  an  excellent 
means  of  killing  the  larvae,  as  they  are  knocked  to  the  ground 
and  large  numbers  killed  by  the  fine  dust.  If  the  field  is  very 
hard  it  is  advisable  to  disk  it  before  using  the  drag.  After  the 
use  of  the  drag,  the  fields  should  be  watered  where  there  is 
irrigation.  In  summarizing  the  methods  of  control,  Professor 
Titus  recommends:     "That  alfalfa  be  disked  in  early  spring  to 

stimulate  it  to  bettergrowth. 
That  the  first  growth  be  cut 
when  the  most  of  the  eggs 
have  been  laid  (middle  of 
May)  and  then  brush-drag 
the  field  thoroughly.  Fields 
should  be  brush-dragged 
again  after  the  first  crop  has 
has  been  cut.  All  weeds 
and  rubbish  should  be  clean- 
ed from  the  fields,  yards, 
ditches  and  fence  rows  so 
that  there  will  be  less  op- 
portunity for  the  weevils  to 
find  winter  shelter.  Alfalfa 
should  not  be  allowed  to 
grow  more  than  seven  or 
eight  years  in  infested 
districts." 

Quarantine  measures  to  prevent  the  spread  are  matters  of 
local  and  state  jurisdiction  but  are  of  the  highest  importance 
to  the  alfalfa  growers  of  the  country.  *" 


Fig. 


166. — The     Clover-mite 
pratensis). 


(Bryobia 


The  Clover-mite  * 

The  Clover-mite  is  nearly  related  to  the  common  red  spider 
of  greenhouses,  with  which  it  is  often  confused,  belonging  to  the 
same  family  of  vegetable-feeding  mites.  It  is,  however,  about 
twice  the  size  of  the  red  spider,  being  four  one-hundredths  inch 

*  Bryobia  pratensis  Garman.     Family  Tetranychidoe.     See  C.  L.  Marlatt, 
Circular  19,  2d  Ser.,  Division  of  Entomology,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  CLOVER  AND  ALFALFA         199 

long.  Though  known  as  the  clover  mite,  on  account  of  its  feed- 
ing upon  that  plant,  yet  this  insect  was  first  known  as,  and 
is  still,  an  important  enemy  of  fruit-trees,  more  especially  on  the 
Pacific  coast,  but  also  in  other  sections  of  the  country.  The  most 
injury  seems  to  have  been  done  to  clover  in  the  Central  States  as 
far  south  as  Tennessee,  though  it  has  suffered  somewhat  even 
in  the  East. 

When  attacked  by  the  mite  the  leaves  of  clover  or  fruit- 
trees  become  yellow  and  have  a  sickly  appearance,  as  if  affected 
with  a  fungous  disease.  Especially  upon  the  upper  sides  of  the 
tender  leaves  of  clover  the  juices  are  extracted  over  irregular 
areas,  looking  more  or  less  Hke  the  burrows  of  some  leaf-mining 
larvae.  Owing  to  the  small  size  of  the  mites  they  may  be  doing 
considerable  damage  to  the  foliage  and  yet  remain  unnoticed; 
but  in  the  egg  stage  the  pest  is  much  more  readily  detected  and 
attacked.  In  the  more  northern  States  the  eggs  are  laid  in  the 
fall,  and  do  not  hatch  until  the  next  spring.  Farther  south, 
however,  the  adult  mites  hibernate  over  winter.  The  eggs  are 
of  a  reddish  color,  laid  upon  the  bark  of  trees,  especially  in  the 
crotches,  and  in  the  West  are  sometimes  so  thickly  placed  as 
to  cover  considerable  areas  two  or  three  layers  deep. 

When  the  adult  mites  leave  the  clover-fields  in  the  fall  to 
find  hibernating  quarters  upon  fruit-trees  for  the  winter,  they 
often  become  quite  a  nuisance  by  invading  dwelling-houses 
which  are  in  their  path.  This  is  more  particularly  the  case 
throughout  the  Mississippi  Valley. 

Remedies. — The  only  practical  way  of  protecting  clover  from 
the  mite  is  by  destroying  the  eggs  and  hibernating  mites  upon 
the  fruit-trees  in  winter.  This  may  be  done  by  burning  all  the 
prunings  and  thoroughly  spraying  the  trees  with  kerosene  emul- 
sion diluted  with  five  parts  of  water,  or  with  miscible  oils  or 
lime-sulfur  mixture.  Such  a  spraying  will  also  protect  the  fruit- 
trees  from  the  mite,  and  will  destroy  numerous  other  insects, 
such  as  the  pear-leaf  bUster-mite,  which  hibernates  upon  the 
trees.  Such  small  insects,  so  minute  as  usually  to  escape  notice, 
are  often  responsible  for  a  poor  growth,  and  should  be  properly 
checked  whenever  known  to  be  injurious. 


200       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Clover-seed  Midge  * 

The  Clover-seed  Midge  seems  to  occur  wherever  red  and 
white  clover  is  grown  in  this  country,  and  is  a  pest  which  must 
be  taken  into  consideration  in  raising  seed,  for  frequently  it  is 
not  recognized  as  the  cause  of  the  failure  of  the  seed  crop.  Alsike 
clover,  and  probably  mammoth  clover,  is  practically  uninjured, 
as  it  flowers  enough  later  to  escape  attack,  nor  is  alfalfa  infested. 

Life  History. — The  parent  of  all  this  trouble  is  a  small  midge, 
one-twelfth  inch  long,  with  black  head  and  thorax  and  reddish 


Fig.  167. — ^The  clover-flower  midge  (Dasyneura  leguminicola) :  a,  enlarged 
side  view  of  female,  with  scales  denuded,  to  show  more  clearly  the  struc- 
ture; b,  head,  more  highly  magnified,  to  show  structure  of  the  eye,  palpi, 
and  basal  joints  of  antennae;  c,  tip  of  ovipositor,  highly  magnified  and 
showing  at  end  of  next  to  last  joint  the  manner  in  which  it  is  clothed  with 
minute  hairs;  d,  highly  magnified  antennal  joints,  their  minute  hairy 
clothing  shown  on  the  lower  one;  2,  a,  larva  enlarged,  ventral  view; 
b,  head  retracted,  highly  magnified.     (After  Riley.) 

abdomen,  so  small,  indeed,  that  it  will  rarely  be  noticed.  The 
antennae  have  sixteen  or  seventeen  segments,  and  the  wings 
have  but  few  veins,  as  shown  in  Fig.  167.  The  female  bears  a 
slender  retractile  ovipositor  which,  when  extended  from  the  tip 
of  the  abdomen,  is  fully  as  long  as  the  body,  while  the  tip  of  the 
abdomen  of  the  male  is  furnished  with  clasping  organs.  The 
midges  appear  in  late  spring  just  as  the  clover  commences  to 
head.  The  eggs  are  laid  among  the  hairy  spines  of  the  clover- 
head  or  beneath  the  bracts  around  it,  are  yellowish  to  orange 

*  Dasyneura   leguminicola   Lintner.      Family   Cecidomyiidce.     Also   called 
the  Clover-flower  Midge.     See  Farmers'  Bulletin  971,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  CLOVER  AND  ALFALFA        201 

in  color,  of  an  oval  shape,  and  about  one  one-hundredth  inch 
long.  Upon  hatching  the  maggot  works  its  way  into  the  open 
end  of  a  floret,  where  it  sucks  the  forming  seed,  and  prevents 
the  petals  of  the  floret  from  expanding,  so  that  although  some 
of  the  flowers  in  the  head  will  bloom,  the  field  as  a  whole  does 
not  blossom  as  usual.  The  maggot  is  footless,  white  to  orange- 
red  in  color,  and  about  one-tenth  inch  long  when  fuU  grown. 
Upon  becoming  grown  in  late  June  and  the  first  week  of  July 
the  maggots  enter  the  soil  and  just  below  the  surface  make 
tough,  oval,  silken  cocoons,  in  which  they  pupate.  The  pupal 
stage  lasts  about  three  weeks  or  more,  and  the  flies  of  the  second 
generation  appear  in  Central  Illinois  in  late  July  and  early  August, 
being  abundant  as  the  second  crop  of  clover  heads  appear.  The 
eggs  are  laid  in  the  clover  heads  and  hatch  in  about  three  days, 
and  the  second  generation  of  maggots  do  the  worst  damage  to 
the  seed  in  late  August  and  early  September^  in  the  same  manner 
as  did  the  first  generation.  They  become  full  grown  by  frost  and 
either  hibernate  as  full-grown  larvae,  in  which  case  they  pupate 
early  the  next  spring,  or  pupate  before  frost  and  pass  the  winter 
as  pupae  in  the  soil. 

Control. — Fortunately  this  pest  may  be  very  readily  controlled 
by  adapting  the  methods  of  harvesting  so  as  to  destroy  the  devel- 
oping maggots.  If  clover  is  grown  alone  it  should  be  cut  early 
before  the  maggots  have  become  mature  This  results  in  drying, 
up  the  food  plant  and  thus  destroying  the  larvae  and  hastens  the 
development  of  the  second  crop  of  clover  heads,  so  that  the  midges 
of  the  second  generation  have  but  few  green  heads  in  which  to  lay 
their  eggs.  Cutting  need  not  be  done  until  the  field  is  fairly  fresh 
with  bloom,  but  should  not  be  delayed  until  the  flowers  commence 
to  wither.  Where  timothy  and  clover  are  grown  together  they 
should  be  pastured  lightly  or  clipped  back  in  May,  which  will 
result  in  bringing  both  the  first  and  second  blooming  after  the 
greatest  abundance  of  the  midges.  As  the  midges  do  not  travel 
far,  it  would  seem  advisable  to  "prevent  the  sporadic  heading  of 
first-year  clover  by  mowing  it  back  a  few  weeks  after  small  grains 
have  been  harvested,  at  a  time  when  growth  is  vigorous,  but  yet 
sufficiently  early  to  permit  considerable  growth  before  frost  sets 
in.  Volunteer  clover  should  always  be  cut,  as  it  affords  a  rich 
nursery  for  all  kinds  of  clover  insects." — Folsom. 


202       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Clover-seed  Chalcid  * 

Evidence  accumulates  that  the  shortage  of  the  clover-seed 
crop  may  frequently  be  due  to  the  larva  of  a  little  chalcis-fly 

which  hollows  out  the 
ripening  seed,  leaving 
it  brown,  brittle  and 
hollow,  so  that  the  af- 
fected hulls  are  blown 
away  with  the  chaff  in 
threshing.  As  there  is 
no  evidence  of  the  pest 
in  the  appearance  of 
the  heads,  and  as  the 
worst  affected  seed  is 
thus  overlooked  i  n 
threshing,  its  work  will 
often  evade  detection. 


Fig.  168. — ^The  clover-seed  chalcis  (Bruchophagus 
funebris):  adult  female,  much  enlarged; 
antenna  of  male  at  left,  more  enlarged. 
(After  Webster,  U.  S.  Dept.  Agr.) 


If  the  seed  crop  is  short  it  will  be  well  to  examine  seed  for  the 
larvae;  many  of  the  seed  will  be  found  shriveled  and  misshapen, 
and  frequently  considerable  numbers  of  the  adults  will  issue  from 
the  seed  soon  after  threshing. 

The  adult  is  a  small,  wasp-like  fly  one-twelfth  to  one-sixteenth 
inch  long,  black  in  color,  and  with  four  wings,  the  hind-wings  very 
small  and  the  fore-wings  with  but  a  single  vein.  It  belongs  to  a 
family  almost  all  of  which  are  parasitic  on  other  insects,  and  for 
many  years  it  was 
thought  to  be  a  para- 
site of  the  clover-seed 
midge,  until  its  true 
role  was  discovered. 
In  recent  years  exam- 
inations o  f  ripening 
heads  from  all  parts  of 
the  country  show  it  is         '^  ^  ^  ^ 

probably  distributed  ^ig.  16?.-The  clover-seed  chalcis:  a,  egg-highly 
'^  -^  .         magnified;   o,  larva  an,  head  more  enlarged;  c, 

wherever    clover  is      pupa— much  enlarged.     (After  Webster,  U.  S. 
and  that  from      I^^pt.  Agr.) 


grown 

*  Bruchophagus  funebris  Howard. 


Family  Chalcididoe. 


INSECTS  INJURIOUS  TO  CLOVER  AND  ALFALFA         203 

20  to  80  per  cent  of  the  seed  is  often  destroyed.  Both  red  and 
crmison  clovers  are  attacked,  and  a  recent  bulletin  *  from  the 
Department  of  Agriculture  states  that  the  insect  is  actually- 
threatening  to  destroy  the  alfalfa  seed  industry  in  certain  sections 
which  formerly  produced  it  in  quantity. 

Life  History. — The  winter  is  passed  by  the  fully  grown  larvae 
in  seed  on  the  ground.  The  adults  emerge  in  the  spring,  the  maxi- 
mum appearing  about  June  10th  in  central  Illinois,  according  to 
Dr.  Folsom,  to  whom  we  are  indebted  for  the  most  careful  study 
of  the  pest.  The  females  deposit  their  eggs  in  the  soft  seed,  just 
as  the  floret  is  withering,  being  unable  to  penetrate  the  seed  after 
it  has  hardened.  The  egg  is  whitish,  about  .01  inch  long,  and 
with  a  peculiar  tail-like  appendage  (Fig.  169).  The  maggot-hke 
larva  feeds  upon  the  seed,  gradually  hollowing  it  out,  and  when 
full  grown  is  about  one-twelfth  inch  long,  stout  and  footless, 
with  a  small  head.  The  pupal  stage  is  passed  within  the  seed 
and  a  second  generation  of  adults  emerges  about  the  middle  of 
August.  These  lay  their  eggs  in  the  second  growth,  and  some 
of  the  adults  from  these  appear  the  same  season  and  the  rest 
not  until  the  following  year.  There  seem  to  be  at  least  three 
generations  a  year  in  central  Illinois,  but  the  life  history  is  com- 
plicated by  the  irregularity  in  the  time  of  development,  though 
the  greatest  numbers  of  adults  appear  about  June  10th  and 
August  10th,  just  as  the  clover-seed  is  green. 

Control. — Mr.  T.  D.  Urbahns,  in  the  bulletin  mentioned, 
recommends  cutting  the  seed  crop  promptly  and  stacking  it  as 
soon  as  possible,  using  well  cleaned  seed,  destroying  burr-clover 
and  cleaning  up  of  waste  land  as  well  as  destruction  of  screenings 
from  the  thresher  and  winter  cultivation  as  being  practices  likely 
to  reduce  the  damage  from  the  chalcis.  He  particularly  recom- 
mends that  infested  crops  be  harvested,  even  if  they  are  of  no 
value  for  seed,  since,  if  they  are  left  standing  and  pastured  they 
will  infest  a  whole  locahty. 

The  Clover-seed  Caterpillar  f 

"In  its  ability  to  diminish  the  seed  crop,  this  pest  ranks  with 

the  seed-midge  and  the  seed-chalcid.     Attacking  a  clover  head 

that  is  green  or  partly  in  bloom,  the  Httle  caterpillar  eats  out  a 

*  Farmers'  Bulletin  636,  U.JS.  Dept.  Agr. 

t  Enarmonia  interstinctana  Clem.     Family  Grapholithidce. 


204       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


cavity  in  the  head,  destroying  many  of  the  unopened  buds  and 
some  of  the  tender  green  seeds,  and  spoiHng  the  head  as  a  whole. 
When  no  young  clover  heads  are  at  hand,  the  caterpillar  feeds 
on  tender  green  leaves  at  the  crown  of  the  plant." — Folsom. 
Red  clover  is  the  principal  food  plant,  but  white,  alsike,  and 
probably  mammoth  clovers  are  also  affected.  The  pubUshed 
records  show  that  it  occurs  in  the  Northeastern  States  southwest 
to  Missouri,  but  it  doubtless  occurs  elsewhere  where  clover  is 
grown,  as  it  might  readily  be  carried  in  hay. 

Life  History. — The  adult  is  a  pretty  little  brown  moth,  with 
a  wing  expanse  of  two-fifths  inch,  with  silvery  markings  as  shown 

in  Fig.  170,  the  most  conspicuous 
marks  forming  a  double  crescent 
when  the  wings  are  closed  on  the 
back.  The  moths  appear  about 
the  end  of  May  in  central  Illinois, 
or  just  as  the  clover  is  coming  in- 
to bloom,  being  active  in  early 
evening,  when  the  females  lay 
their  eggs  in  the  heads.  The  egg 
is  circular  in  shape,  about  .01  inch 
in  diameter,  yellowish-white  in 
color,  and  hatches  in  five  or  six 
days.  In  first-year  clover  that  has 
not  headed  and  in  second-year 
clover  recently  cut,  the  eggs  are 
laid  on  young  stems  and  leaflets 
at  the  base  of  the  plant,  where  the  larvse  stay. 

"Hatching  usually  at  the  base  of  a  green  clover-head;  the 
larva  eats  into  the  head,  destroying  the  green  florets  as  it  goes. 
A  small  green  head  is  often  destroyed  entirely,  before  it  is  many 
days  old;  a  larger  head  is  injured  only  locally  at  first,  remaining 
green  on  one  side,  while  the  other  and  unaffected  side  may  come 
into  full  bloom."  Judging  from  the  appearance  of  the  head  the 
work  might  be  that  of  the  seed-midge,  but  whereas  it  is  hidden 
away  in  a  single  floret,  this  caterpillar  makes  a  large  dirty  excava- 
tion involving  many  florets,  and  is  readily  found  by  tearing  open 
the  head.  The  caterpillar  attacks  the  bases  of  the  florets,  includ- 
ing the  semifluid  ovules,  but  does  not  attack  seeds  which  have 


Fig.  170 — Clover-seed  caterpillar  (En- 
armonia  interstinctana) :  a,  cater- 
pillar: h,  pupa;  c,  moth,  all  much 
enlarged:  d,  moth  natural  size. 
(After  Osborn.) 


INSECTS  INJURIOUS  TO  CLOVER  AND  ALFALFA    205 

hardened.  "Even  when  the  direct  injury  is  confined  to  a  portion 
of  the  clover-head,  the  entire  head  is  ruined,  for  it  at  length  dries 
up  and  loses  the  rest  of  the  florets,  leaving  only  the  dead  and 
brown  receptacle.  Less  conspicuous,  though  not  inconsiderable, 
is  the  injury  at  the  crown  of  the  plant,  done  chiefly  in  September 
and  October,  by  caterpillars  of  the  same  species  feeding  upon  the 
leaves." — Folsom.  The  total  injury  varies  greatly,  but  not  infre- 
quently 20  per  cent  of  the  heads  are  infested,  and  in  Iowa  infesta- 
tion has  sometimes  been  exceedingly  severe.  In  any  event,  every 
head  destroyed  means  the  loss  of  more  than  one  hundred  seeds. 

The  larvae  become  full  grown  in  four  to  five  weeks.  The  full 
grown  caterpillar  is  about  one-third  inch  long  and  varies  in  color 
from  dirty-white  tinged  with  green  to  orange,  according  to  the 
food.  The  larva  spins  an  oval  white  silken  cocoon,  two-fifths 
inch  long,  either  in  the  head  or  at  the  surface  of  the  ground, 
which  is  more  or  less  covered  with  bits  of  excrement  and  floral 
tissue.  The  pupa  is  one-fifth  inch  long,  brown,  with  the  thorax 
and  wing-cases  darker,  and  with  two  transverse  rows  of  teeth 
on  the  back  of  the  abdominal  segments  except  the  last,  which 
bears  six  stout  blackish  hooks  at  the  tip.  The  pupal  stage  lasts 
two  to  three  weeks  and  a  second  generation  of  moths  emerges 
about  the  third  week  of  July  (in  central  Illinois).  The  Kfe  cycle 
is  repeated  in  the  same  manner  and  a  third  generation  of  moths 
appears  about  September  1st.  The  larvse  of  the  last  brood  feed 
either  in  immature  clover-heads  or  at  the  crown  of  the  plant. 
Most  of  them  become  full  grown  and  transform  into  pups,  in 
which  stage  they  hibernate  over  winter,  while  others  become  full 
grown,  but  fail  to  pupate  and  hibernate  under  rubbish. 

Control. — Cutting  and  storing  the  hay  crop  early  in  June  as 
advised  for  the  clover-seed  midge  will  kill  the  larvae  while  stiU 
in  the  heads.  ''The  hay  should  be  handled  Hghtly  and  stacked 
or  stored  as  soon  as  possible.  Osborn  and  Gossard  *  have  at- 
tested the  value  of  this  method,  and  have  given  these  further 
recommendations:  (1)  Cut  volunteer  clover  in  early  June  and 
dispose  of  the  heads  speedily;  (2)  do  not  allow  clover  to  run  for 
more  than  two  years;  (3)  sow  seed  on  land  remote  from  old 
fields;    (4)  pasture  clover  in  the  fall  of  the  first  year;    (5)  plow 

*  Osborn  and  Gossard,  Insect  Life,  Vol.  IV,  p.  254;  Bulletins  14  and  15, 
Iowa  Agr.  Exp.  Sta.;  22d  Report  Entomological  Society  of  Ontario,  p.  74. 
Gossard,  H.  A.,  Bulletin  19,  Iowa  Agr.  Exp.  Sta. 


206       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

an  old  clover-field  under  in  October  or  November  or  in  early- 
spring,  then  harrow  and  roll.  These  practices  operate  at  the 
same  time  against  several  other  clover  pests." — Folsom. 


The  Clover-hay  Worm  * 

The  Clover-hay  Worm  attatiks  stacked  or  stored  clover,  par- 
ticularly where  it  is  held  over  a  year  or  where  placed  oh  old  hay, 
eating  much  of  the  lower  layers  and  rendering  it  unfit  for  food. 


1 

,  >; 

1 

H 

^i^«^   7 

|7?^ 

f             ■ 

:...,.  ^ 

_^ 

Fig.  171. — Clover-hay  worm,  greatly  enlarged.    (After  Folsom.) 

It  has  been  known  to  be  injurious  from  Kansas  eastwaid,  but 
occurs  throughout  most  of  North  America,  as  well  as  parts  of 
Europe,  Asia,  and  Africa. 


Fig.  172. — The  clover-hay  worm  moth,  wings  expanded  (after  Folsom)  and 
at  rest  (after  Pettit) — enlarged. 

"The  larvae  attack  the  bottom  of  a  clover  stack  to  a  height 
of  2  feet  or  more  from  the  ground;  similarly,  in  the  barn,  they 
occur  next  the  floor.  They  interweave  the  hay  with  white  silken 
webs,  intermixed  with  black  grains  of  excrement.  .  .  ;  they 
reduce  much  of  the  hay  to  chaff,  and  their  webs  give  the  hay 

*  Hypsopygia  costalis  Fab.     Family  Pyralididoe. 


INSECTS  INJURIOUS  TO  CLOVER  AND  ALFALFA        207 

the  appearance  of  being  mouldy;  in  fact,  such  hay  actually 
becomes  mouldy  if  it  has  been  lying  near  the  ground.  This  hay 
is  refused  by  horses  and  cattle  and  is  fit  only  to  be  burnt.  When 
the  hay  is  removed,  swarms  of  wriggling  brown  caterpillars  are 
left."  The  work  of  the  caterpillars  is  usually  noticed  in  late 
winter  and  spring. 

Life  Histonj. — The  moths  appear  from  the  middle  of  June 
until  early  July  in  the  Northern  States  and  most  of  the  first 
generation  have  disappeared  by  the  end  of  July.  The  moths 
have  a  wing  expanse  just  under  an  inch,  with  silky,  wings  tinged 
with  purplish  above,  margined  with  orange  and  fringed  with 
golden-yellow.  On  each  side  of  the  fore-wings  are  two  large, 
golden  spots  which  divide  the  anterior  margin  into  thirds  and 
continue  backward  as  narrow  lilac  lines  (Fig  172).  The  hind- 
wings  are  marked  by  two  transverse,  wavy,  straw-colored  lines. 

As  soon  as  some  clover-hay  is  found  the  female  deposits  her 
eggs  and  the  caterpillars  feed  upon  it.  When  full  grown  they 
are  about  three-quarters  inch  long,  of  a  dull-brown  color.  The 
segments  are  divided  by  a  transverse  groove,  and  each  bears 
several  shining  areas,  with  a  fine  white  hair  in  each.  White 
silken  cocoons,  one-haK  inch  long,  covered  with  bits  of  hay  and 
excrement,  are  made  by  the  larvae  in  the  hay  or  in  cracks  and 
crevices  of  the  barn,  in  which  they  transform  to  pupae,  which 
are  of  a  honey-yellow  color,  with  the  parts  clearly  defined  by 
the  darker  color  of  the  sutures.  The  moths  of  the  second  brood 
emerge  from  the  middle  of  August  until  September  1st,  but  may 
be  found  flying  until  late  October.  Caterpillars  of  all  sizes  may 
be  found  in  barns  throughout  the  winter  and  pupate  in  the  spring. 

Control. — Usually  no  serious  injury  is  done  except  where 
clover-hay  is  kept  over  the  second  year  or  longer.  When  it  is 
fed  out  each  spring,  before  the  next  crop  is  harvested,  there  is 
no  food  for  the  young  caterpillars,  and  they  perish  before  the 
new  crop  comes  in.  Consequently  mows  should  be  cleaned  out 
each  spring.  New  clover-hay  should  never  be  placed  on  top  of 
old  hay,  and  stacks  should  be  placed  at  some  little  distance 
from  the  old  stacks  if  possible.  Burn  up  the  refuse  from  old 
stacks,  or  what  remains  in  the  bottom  of  the  mow.  Stacks 
should  be  raised  above  the  ground  on  a  foundation  of  logs  or 
rails,  so  as  to  keep  the  bottom  as  dry  and  cool  as  possible,  as 


208       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

the  caterpillars  love  warmth  and  moisture.  It  has  been  found 
that  salting  the  hay  for  2  or  3  feet  at  the  bottom  will  prevent 
injury,  and  many  farmers  salt  their  clover-hay,  using  about  two 
quarts  of  salt  to  the  ton. 

The  Clover  Leafhopper  * 

The  Clover  Leafhopper  is  an  insect  which  may  be  found  in 
clover  and  alfalfa  fields  over  a  wide  range.  It  is  a  very  small 
insect,  like  most  common  leafhoppers,  and  its  injury  is  widely 
distributed,  so  that  it  often  attracts  no  notice,  but  is  none  the 
less  real.  The  insects  are  slender  forms,  one-eighth  inch  in 
length  and  of  a  grayish  color  with  darker  markings.  They  hop 
actively  when  disturbed  and  may,  at  times,  be  noticed  in  clouds 
when  one  walks  through  a  clover  field. 

Injury. — The  injury  is  caused  in  two  ways.  First,  they  suck 
the  sap  from  the  stems  and  foliage  of  the  plant  and,  later,  they 


Fig.  173. — The  clover  leafhopper  {Agallia  sanguinolenta) :  a,  adult;  6,  nymph, 
side  view;  c,  nymph,  dorsal  view;  d,  face;  e,  elytron;  /,  female  geni- 
talia; g,  male  genitalia.  All  enlarged.  (After  Osborn  and  Ball,  from 
Gibson,  1.  c.) 

puncture  the  tissues  and  deposit  their  eggs  within  them,  the 
result  being  irregular  swellings  which  interfere  with  the  growth. 

Life  History. — There  are  at  least  three  generations  but  they 
are  more  or  less  indistinguishable  on  account  of  over-lapping. 
They  hibernate  as  adults.  The  young  or  nymphs  resemble  the 
adults  in  a  general  way  but  are  greener  in  color  and  less  active. 

Control. — Clean  culture,  burning  of  rubbish  in  the  fall  and 
early  cutting  of  the  clover  and  alfalfa  as  well  as  close  pasturing 

*  Agallia  sanguinolenta  Prov.     Family  Jassidce. 


INSECTS  INJURIOUS  TO  CLOVER  AND  ALFALFA 


209 


of  grass  lands  while  the  adults  are  numerous  are  the  Bureau  of 
Entomology  recommendations  for  control.* 

When  leafhoppers  are  unusually  numerous  and  destructive 
they  may  be  captured  in  enormous  numbers  by  the  use  of  a 
hopperdozer  or  hopperette,  constructed  along  the  same  lines  as 
those  used  for  grasshoppers. 

Miscellaneous  Insects  of  Clover  and  Alfalfa 

In  addition  to  the  insects  already  discussed  there  are  many 
others  which  attack  these  crops,  either  occasionally  or  regularly. 
Among  these  should  be  mentioned  the  grasshoppers,  a  complete 
discussion  of  which  will  be  found  in  Chapter  VII,  the  pea-louse, 


Fig.  174. — The  alfalfa  caterpillar:    full-grown  larva.     Enlarged  about  three 
diameters.     (After  Wildermuth,  1.  c.) 

which  is  fully  discussed  in  Chapter  XV,  and  the  blister  beetles, 
also  discussed  in  Chapter  XV  and  the  one  following  and  in  Chap- 
ter VII.  Besides  these  there  are  several  species  of  caterpillars 
found  in  greater  or  less  abundance  in  clover  and  alfalfa  at  all 
times.     These  include  the  following: 

The  Alfalfa  Caterpillar  f  which  is  the  larva  of  one  of  our 
most  common  yellow  butterflies  always  associated  with  clover 
fields  and  so  familiar  to  all  as  to  need  no  description.  The  larva 
is  green  in  color  and  similar  to  the  common  cabbage  worm,  dif- 
fering in  the  possession  of  a  light  stripe  on  each  side  through 
which  runs  a  bright  red  Hne.  The  insects  seem  to  hibernate  in 
all  stages  and  there  are  two  or  more  broods. 

Damage  to  the  crops  is  usually  not  severe  in  any  one  place 
but  evenly  distributed  and  aggregates  more  than  would  be  sup- 

*  See  Farmers'  Bulletin  7.37,  U.  S.  Dept.  Agr. 

t  Eurymus  eurytheme  Boisd.  Family  Pieridae.  See  V.  L.  Wildermuth, 
U.  S.  Dept.  Agr.  Bulletin  124. 


210       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


posed.     In  some  localities  damage  is  severe  and  control  measures 
must  be  employed.     When  this  is  necessary  the  following  prac- 


Fig.    175. — Map    showing    distribution    of    the    alfalfa 
caterpillar.     (After  Wildermuth,  1.  c.) 

tices  are  advisable:    Cut  the  crop  early  and  close  to  the  ground; 
pasture  closely  where  possible;  disk  badly  infested  fields  and 


Fig.  176. — Map  showing  distribution  of  the  green  clover 
worm  in  the  United  States.     After  Hill.) 

then  run  over  them  a  roller  or  a  brush  drag;  keep  cultural  con- 
ditions in  a  high  state  of  perfection  at  all  times. 


INSECTS  INJURIOUS  TO  CLOVER  AND  ALFALFA        211 

The  Green  Clover-worm  *  is  another  caterpillar  which  is 
frequently  abundant  in  fields  of  clover,  alfalfa,  soy  beans  and 
related  crops.  It  is  a  green  caterpillar  with  darker  stripes,  an 
inch  or  more  in  length  and  the  larva  of  one  of  the  common  dull- 
colored  moths  of  the  cutworm  type.  It  is  best  controlled  by 
harvesting  the  crop  when  the  worms  are  present  in  the  greatest 
abundance  but  are  not  quite  grown,  whether  the  crop  is  quite 
ready  to  cut  or  not.  In  this  way  many  are  starved  and  others 
perish  from  exposure  to  the  sun  after  the  crop  has  been  removed. 
Supplement  this  with  the  brush  drag  if  the  worms  are  especially 
numerous. 

The  Alfalfa  Looper  f  is  one  of  the  serious  occasional  pests 
of  aKalfa  in  the  Northwest. 
It  is  abundant  mainly  in 
irrigated  regions.  Control 
measures  recommended 
are  similar  to  those  for  the 
green  clover-worm  and  al- 
falfa caterpillar  and  are  at 
times  supplemented  by  the 
use  of  poisons.  Fig.  177. — The  green  clover  worm;  adult  or 

The  Garden  Webworm        ™°^^-  ^^"^^  enlarged.    (After  Hill). 

(See  Chapter  XIX)  sometimes  defoUates  aKalfa  and  related 
plants  and  leaves  over  the  injured  stalks  the  webs  which  serve 
to  identify  it.  Control  measures  applicable  to  it  are  almost 
exactly  similar  to  those  for  the  other  caterpillars  Usted. 

*  Plathypena  scabra  Fabr.  Family  Noctuidae.  See  Farmers'  Bulletin 
No.  982,  U.  S.  Dept.  Agr. 

t  Autographa  calif ornica  Speyer.  Family  Noctuidae.  See  J.  R.  Parker 
Jour.  Econ.  Ent.,  Vol.  8,  No.  2,  1915. 


CHAPTER  XII 


INSECTS  INJURIOUS  TO  TOBACCO  * 

The  Tobacco  Flea-beetle  f 

The  Tobacco  Flea-beetle  is  one  of  the  important  pests  of  that 
plant  throughout  the  Middle  States,  being  particularly  injurious 

to  young  plants.  The  beetles 
damage  the  leaves  by  eating 
small  holes  in  the  upper  or  un- 
der surfaces,  or  clear  through 
them,  so  that  when  badly 
eaten  the  leaves  look  as  if  they 
had  been  peppered  with  shot. 
The  little  beetles  which  do 
this  damage  are  hardly  more 
than  one-twentieth  inch  long 
light  brown  in  color,  with  a 
dark  band  across  the  wing- 
covers.     A  few  of  them  could 

Fig  178.— Tobacco  nea-heetleiEpitrix  par-  do  but  little  damage,  but  they 
vula):  a,  adult  beetle;  b,  larva  lateral 

view;  c,  head  of  larva;  d,  posterior  leg  soon  mcrease  m  numbers,  so 
of  same;  e,  anal  segment,  dorsal  view;  that  they  SWarm  over  the 
/,  pupa — a,  b,  f,  enlarged  about  fifteen  . 

times;  c,  d,  e,  more  enlarged.  (After  leaves  and  mjure  them  badly. 
Chittenden,  U.  S.  Dept.  Agr.)  Similar    injury    is    done    to 

potato,  egg-plant,  and  tomato,  and  the  beetles  also  feed  on  horse- 
nettle,  nightshade,  and  Jamestown  weed. 

Life  History — The  eggs  are  laid  in  the  soil  and  the  larvae  feed 
upon  the  roots  of  common  weeds,  such  as  the  nightshade  and 
Jamestown  weed.     The  larva  is  delicate,  thread-like  and  white, 

*  See  L.  O.  Howard,  Farmers'  Bulletin  120,  U.  S.  Dept.  Agr.,  The  Prin- 
cipal Insects  Affecting  the  Tobacco  Plant.  A.  C.  Morgan,  Circular  123, 
Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  Yearbook,  U.  S.  Dept.  Agr.,  1910, 
pp.  281-296;  and  Z.  P.  Metcalf,  N.  C.  Dept.  of  Agr.  Bulletin,  Oct.,    1909. 

t  Epttrix  parvula  Fab.     Family  Chrysomelidae. 

212 


INSECTS  INJURIOUS  TO  TOBACCO 


213 


except  the  yellowish  head,  and  about  one-eighth  inch  long.  It 
pupates  in  the  soil.  When  the  beetles 
become  very  numerous  the  larvae  some- 
times develop  on  the  roots  of  tobacco, 
but  rarely  do  serious  damage.  The 
life  history  has  not  been  determined 
exactly,  but  the  full  life  cycle  seems 
to  occupy  about  a  month,  so  that 
there  are  probably  several  generations 
in  a  year. 

Control. — Inasmuch  as  the  larvae 
develop  on  the  roots  of  the  weeds 
mentioned,  it  is  evident  that  they 
should  be  kept  down  by  thorough  cul- 
tivation. Where  the  beetles  appear, 
the  plants  should  be  sprayed  or  dusted 
with  Paris  green,  or  probably  better, 
arsenate  of  lead,  the  same  as  for  the 
horn-worm.  Dipping  the  plants  in 
arsenate  of  lead,  1  pound  to  10  gal- 
lons of  water,  just  as  they  are  set,  has 
been  found  to  afford  very  satisfactory 
protection  in  Connecticut. 

The  Tobacco  Stalk-worm  * 

Professor  W.  G.  Johnson  found  this' 
species,  also  known  as  the  Corn-root 
Web  worm,  to  be  a  serious  pest  to  grow- 
ing tobacco-plants  in  southern  Mary- 
land, where  it  seems  to  have  been  a 
tobacco  pest  for  a  good  many  years, 
and  it  has  also  been  noted  in  Delaware. 

The  Injury.— The  injury  to  tobacco    Fig.  179.— T  o  b  a  c  c  o  leaves 

,         -111       -n>     c  T  1  damaged  by  Evitrix  parvul. 

IS  described  by  Professor  Johnson  as       (After  Howard,  U.  S.  Dept. 

follows:  "The  uninjured  tobacco  had      ^^^-^ 

a  leaf  spread  of  from  ten  to  twelve  inches.     A  few  rods  beyond, 

where  the  soil  was  not  so  gravelly  and  better,  we  found  the  larvae 

*  Crambus  caloginosellus  Clem.     Family  Cramhidce.     See  p.  161  and  Bul- 
letin 20,  n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr.,  pp.  99-101,  1899. 


214       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

had  literally  destroyed  the  first  and  second  plantings  and  were 
at  work  upon  the  third,  damaging  it  severely,  although  the  ground 
had  been  replanted  before  the  last  planting.  Here  and  there  was 
a  young  plant  just  beginning  to  wilt,  and  invariably  we  found  the 
larva  at  work  either  in  the  stalk  or  at  the  base  of  the  plant  just 
below  the  surface  of  the  ground.  So  far  as  I  could  ascertain,  the 
attack  is  always  at  the  surface  or  just  below.  In  many  instances 
the  larvae  had  hollowed  out  the  stalks  from  the  base  of  the  roots  to 
the  branches  of  the  first  leaves.  Many  plants  were  gnawed 
irregularly  around  the  stalk  below  the  surface,  and  some,  in  fact, 
were  completely  cut  off  at  the  surface,  the  insect  always  working 
from  below.  In  the  great  majority  of  cases  the  larvae  were  found 
in  a  small  mass  of  web  near  the  plant,  and  sometimes  within 
it.  In  one  plant,  less  than  six  inches  high,  we  found  four 
larvae  within  the  stalk,  but  as  a  rule  only  a  single  one  was 
present." 

Professor  Johnson  concluded  "(1)  that  it  is  most  likely  to 
occur  over  local  areas  in  tobacco  following  timothy  or  grass; 
(2)  that  the  character  of  the  soil  has  little  or  nothing  to  do  with 
its  ravages;  (3)  that  the  attack  upon  corn  is  also  a  frequent 
occurrence  in  the  same  section;  especially  when  following  grass 
or  timothy." 

Remedies. — He  recommended  "(1)  that  growers  of  tobacco 
avoid  planting  upon  grass  or  timothy  sod;  (2)  that  where  grass 
land  is  plowed  down  it  would  be  well  to  put  it  in  wheat,  following 
with  clover,  before  tobacco.  If  desirable,  corn  could  follow 
the  grass  and  the  land  could  be  seeded  in  crimson  clover  at  the 
last  working.  This  would  serve  a  twofold  object  by  revealing 
the  exact  location  of  larvae  in  the  area  under  cultivation  by  their 
attack  upon  corn,  when  they  could  be  destroyed  largely  by 
frequent  harrowing  and  rolling,  and  by  affording  a  most  excellent 
soil  crop  to  turn  down  the  following  spring,  which  would  be  a 
decided  advantage  to  the  tobacco;  that  if  it  is  found  neces- 
sary to  have  tobacco  following  grass,  it  should  be  broken  in 
the  spring  as  early  as  possible,  and  frequently  rolled  and  har- 
rowed, at  the  same  time  delaying  the  setting  of  the  plants  as  long 
as  possible  in  order  to  destroy  and  starve  the  larvae  within  the 
ground." 


INSECTS  INJURIOUS  TO  TOBACCO 


215 


The  Spined  Tobacco-bug  * 

Professor  H.  Garman  has  found  a  small  bug,  which  he  has 
termed  the  Spined  Tobacco-bug,  doing  more  or  less  injury  to  plants 
in  Kentucky,  and  as  this  insect  is  widely  distributed  throughout  the 
country,  it  probably  does  more  or  less  damage  elsewhere,  though 
never  a  serious  pest.  Concerning  its  work,  he  says:  "Occa- 
sional plants  in  tobacco-fields  are  at  times  observed  to  have  become 
suddenly  wilted,  the  leaves  hanging  hmp,  much  as  if  the  stalk  had 
been  severed.  After  a  time  they  recover  again,  and,  beyond  a 
temporary  check  on  their  growth,  appear  to  have  suffered  but 
little  injury.  If  such  plants  are  searched  carefully  while  still 
wilted,  a  flat,  brown  bug  with  each  side  of  the  body  produced  into 
an  angle,  or  sharp  spine,  will  be  found  upon  the  stalk  along  the 
base  of  the  leaves.     It  is  very  shy  and  keeps  out  of  sight,  hence  any 


Fig.  ISO. — The  spined  tobacco-bug  {Euschistus  variolarius) ,  njmaph  at  left; 
adult  at  right — enlarged.     (After  Howard,  U.  S.  Dept.  Agr.) 

brisk  movement  on  the  injured  plants  is  likely  to  cause  it  to  drop  to 
the  ground  and  conceal  itself."  These  insects  are  true  bugs,  suck- 
ing their  food  through  a  beak,  which  is  bent  under  the  body 
between  the  legs  when  not  in  use.  They  are  about  half  an  inch 
long,  of  a  drab  color  above  and  greenish  or  yellowish  below. 
Usually  only  one  bug  is  found  on  a  plant,  so  that  the  best  way  to 
prevent  the  injury  is  to  pick  them  from  the  plants,  and  keep 
down  such  weeds  as  thistles  and  mulleins,  upon  which  such  in- 
sects feed,  in  the  adjoining  fields. 

*  Evischistus.  punctipes  Say  {variolarius  Pal.  Beauv.).     Family  Pentatomidce. 
See  Bulletin  No.  66,  Ky.  Agr.  Exp.  Sta.,  p.  33. 


216       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Homworms  or  Tobacco-worms  * 

Of  all  the  insects  feeding  upon  tobacco,  the  Hornworms  are 
the  most  widely  injurious  and  therefore  best  known.  The  cater- 
pillars of  two  species  of  moths  are  commonly  included  under  this 
popular  name,  both  species  occurring  throughout  the  tobacco- 
growing  States,  the  northern  tobacco-worm  being  more  common 
in  the  North  and  the  southern  tobacco-worm  more  common  in  the 


Fig.  181. — Northern  tobacco-worm,  or  "hornworm"  (Phlegefhontius  quinque- 
maculnta):  a,  adult  moth;  b,  full-grown  larva:  c.  pupa — natural  size. 
(After  Howard,  U.  S.  Dept.  Agr.) 

South.     The  differences  in  the  adult  moths  may  be  readily  appre- 

caited  from  Figs.  181  and  182,  the  southern  form  being  darker  and 

with  brighter  orange  spots  on  the  abdomen,  and  the  white  lines  on 

the  hind-wings  being  less  distinct.     The  larvse  of  both  species 

commonly  attack  tomato  vines  and  are  commonly  called  tomato 

worms  where  tobacco  is  not  grown. 

*  Phlegethontius    quinquemaculata    Haworth     (Northern),    and    P.    sexta 
Johanssen  (Southern).     Family  Sphingidce. 

216 


INSECTS  INJURIOUS  TO  TOBACCO 


217 


Life  History. — The  pupse  pass  the  winter  several  inches  below 
the  surface  of  the  soi)  and  from  them  the  moths  emerge  in  May  and 
June,  according  to  the  latitude  and  season.  The  females  deposit 
their  eggs  singly,  upon  the  lower  surfaces  of  the  leaves,  from  which 
the  little  caterpillars  hatch  in  from  four  to  eight  days.  The  char- 
acteristic work  of  the  larvre  is  too  well  known  to  every  tobacco 
grower  to  necessitate  description.  The  caterpillars  become  full 
grown  in  about  three  weeks,  during  which  time  thev  moult  some 


Fig.  182. — Southern  tobacco-worm  (Phlegethontius  sexia):  a,  adult  moth; 
h,  full-grown  larva;  c,  pupa — natural  size.  (After  Howard,  U.  S.  Dept. 
Agr.) 

five  times.  The  full  grown  larvae  are  three  to  four  inches  long,  of 
a  dark  green  color  with  white  stripes  on  the  side  of  the  body,  those 
of  the  northern  species  having  a  V-shape,  while  those  of  the  south- 
ern species  being  simple  oblique  hands.  At  the  tip  of  the  abdomen 
is  a  stout  horn,  from  which  is  derived  the  name  of  hornworm, 
which  in  the  northern  species  is  black  and  in  the  southern  is  red. 
The  pupse  are  formed  in  the  soil,  are  dark  brown,  about  two  inches 
long,  and  have  a  peculiar  handle-like  process,  the   sheath   of  the 


218       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

proboscis,  which  somewhat  resembles  a  horn  and  which  may- 
account  for  the  name  of  "  hornblowers,"  commonly  given  them  in 
Maryland  and  Virginia.  The  pupal  stage  lasts  about  three  weeks, 
when  the  adults  emerge,  the  whole  life  cycle  requiring  from  six  to 
eight  weeks.  Usually  two  generations  occur  in  a  season  through- 
out most  of  the  tobacco  belt,  but  in  the  North  there  seems  to  be 
but  one  generation,  and  in  the  Gulf  States  there  may  be  three 
generations.  Occasionally  the  worms  are  overlooked  in  cutting 
the  tobacco  and  are  carried  into  the  barn,  where  they  may  do 
considerable  injury  even  after  the  tobacco  is  partially  dry. 

Control. — The  most  common  method  of  control  is  hand-pick- 
ing, usually  termed  "worming."  In  seasons  when  the  worms  are 
not  overabundant  this  may  be  the  most  practical  method  of  con- 
trol, but  it  is  both  tiresome  and  expensive,  and  the  planter  has  no 
means  of  predicting  whether  the  worms  will  be  more  or  less  abun- 
dant. Large  flocks  of  turkeys  driven  through  the  fields  will  aid 
most  efficiently  in  this  work. 

In  many  sections  the  worms  are  now  controlled  by  spraying 
or  dusting  with  Paris  green  or  arsenate  of  lead.  More  or  less  popu- 
lar prejudice  against  the  use  of  arsenicals  has  existed,  as  it  was 
thought  the  tobacco  might  be  poisonous  to  the  consumer.  Careful 
chemical  examinations  have  shown,  however,  that  the  amount 
left  on  the  foliage  after  three  sprayings  would  be  far  too  small  to 
have  any  deleterious  effect.  The  same  prejudice  formerly  existed 
against  the  use  of  arsenicals  on  potatoes,  cabbage  and  other  crops 
but  experience  has  shown  it  to  be  unwarranted.  A  real  objection 
to  the  use  of  Paris  green  is  that  it  sometimes  slightly  burns  the 
foliage,  so  that  arsenate  of  lead  will  doubtless  be  found  preferable. 

Morgan*  recommends  dusting  rather  than  spraying  and  con- 
demns the  use  of  Paris  green.  His  summary  of  recommendations 
is  as  follows: 

"Paris  green,  although  an  effective  insecticide,  frequently 
burns  tobacco  very  severely  and  may  reduce  the  value  of  the  crop 
by  as  much  as  50  per  cent  in  exceptional  cases. 

Arsenate  of  lead  never  seriously  injures  tobacco  even  under 
the  most  unfavorable  conditions. 

A  dosage  of  Paris  green  large  enough  to  be  effective  against  horn- 
worms  can  not  be  applied  without  grave  danger  of  burning  tobacco. 

*  Morgan,  A.  C.     Farmer's  Bulletin  867,  U.  S.  Dept.  of  Agr. 


INSECTS  INJURIOUS  TO  TOBACCO 


219 


Paris  green,  which  is  appHcd  in  dust  form  without  a  carrier, 
is  used  at  the  rate  of  from  1  to  2  pounds  per  acre. 


'  \ 


'  I 


Fig.  183.  Hibernation  of  southern  tobacco- worm;  c,  pupa  in  hibernating  cell  in 
soil,  at  the  depth  of  which  pupation  usually  takes  place  in  the  stiffer  soils; 
a,  cross-section  of  pupal  cell  viewed  from  below;  b,  pupal  cell  showing 
entrance  hole  of  larva — two-third  natural  size;  (After  A.  C.  Morgan, 
U.  S.  Dept.  Agr.) 

Arsenate  of  lead  is  safe  and  effective  during  rainy  weather, 
whereas  Paris  green  is  dangerous  and  ineffective. 


220       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


It  is  recommended  that  arsenate  of  lead  be  used  against  the 

tobacco  horn  worms  and  that  it  be  appHed  as  a  dust  or  powder. 
The  dosage  of  arsenate  of  lead  in  powdered  form  varies  from 

3^  pounds  to  5  pounds  per  acre.     If  applied  as  a  spray,  use  from 

3  to  4  pounds  in  100  gallons  of  water. 

To  apply  arsenate  of  lead  in  powdered  form,  without  a  carrier, 

use  a  dust  gun  having 
a  fan  diameter  of  at 
least  10  in-ches  and  a 
special  device  for  pre- 
venting clogging  of  the 
delivery  pipe.  If  a  gun 
with  such  a  device  is 
not  used,  it  will  be 
necessary  to  mix  the 
arsenate  of  lead  thor- 
oughlywith  equal 
parts  of  dry  wood 
ashes. 

Apply  arsenate  of 

lead  when  there  is  no  breeze  and  when  dew  is  on  the  plants. 

Use  only  such  brands  of  arsenate  of  lead  as  are  guaranteed  to 

contain  at  least  30  per  cent  of  arsenic  oxid,  of  which  not  more  than 

1  per  cent  is  free,  or  water-soluble." 

Natural  Enemies. — Very  frequently  worms  are  found  covered 

with  what  seem  to  be  small,  white  eggs.  These  are  not  eggs,  how- 
ever, but  are  the  small  silken  cocoons 

of  a  little  wasp-like  parasite  (Apan- 

teles   congregatus)  whose  larvae  feedj 

internally   upon  the   juices  of  the 

worm  and  thus  ultimately  kill  it 

before  it  transforms  to  a  pupa.    Such 

parasitized  worms  should  never  be  Fiq,  185.— Southern  tobacco-worm 

destroyed,  as  the   parasites  are  of         with    cocoons    of   parasite. 
1         J.I.        xi-       J  XT-  (After  Garman.) 

more  value  than  the    damage   the 

worm  might  do.  Very  frequently  the  caterpillars  are  attacked  by 
a  bacterial  disease  which  causes  them  to  turn  dark  and  become 
shrunken  and  flaccid. 


Fig.  184. — Southern  tobacco-worm  killed  by 
fungus.     (After  Garman.) 


INSECTS  INJURIOUS  TO  TOBACCO 


221 


Fig, 


b 

186. — The  true  budworm  (Chloridea  vire- 
scens):  a,  adult  moth;  b,  full-grown  larva, 
from  side ;c,  same,  from  above;  d,  seed-pod 
bored  into  by  larva;  e,  pupa — natural  size. 
(After  Howard,  U.  S.  Dept.  Agr.) 


The  Budworms  * 

Two  caterpillars  of  the  same  genus  commonly  attack  the  bud 
of  tobacco  and  have  been  distinguished  by  Dr.  L.  O.  Howard  as 
the  true  budworm  and 
false  budworm,  the  latter 
being  the  same  as  the 
well-known  cotton  boll- 
worm  or  corn  ear-worm. f 

"The  true  budworm 
(Chloridea  virescens)  oc- 
curs in  the  more  south- 
ern portions  of  the  to- 
bacco-growing regions," 
says  Dr.  Howard,t  "  but 
has  not  been  noted  in  to- 
bacco-fields north  of 
Maryland.  The  adult  insect  is  a  small  greenish  moth,  well  illus- 
trated in  Fig.  186.  The  larva  or  caterpillar  of  this  moth,  also  illus- 
trated, is  nearly  always  found  in  the  bud  of  the  tobacco-plant  about 
the  time  the  plant  is  ready  to  top.  In  some  seasons  they  occur  in 
large  numbers  and  damage  the  tobacco  considerably.  In  the 
early  part  of  the  season,  as  a  general  thing,  but  few  of  them  are 
found,  and  in  ordinary  seasons  they  are  not  especially  noticed 
during  the  early"  worming"  of  the  tobacco.  In  August  they 
begin  to  be  more  abundant,  and  generally  leave  the  plant  about 
the  end  of  the  month,  entering  the  ground,  transforming  to  pupae 
and  issuing  as  moths  toward  the  end  of  September.  These  dates 
are  for  Virginia,  but  hold  reasonably  well  as  far  south  as  Mississippi. 
The  greatest  damage  done  by  this  insect  is  by  the  August  brood, 
when  it  enters  the  rolled-up  leaves  or  bud  of  the  plant.  In 
September  and  October  the  next  generation  of  caterpillars  is  found 
boring  into  the  seedpod  and  occasionally  into  the  flower-stem .  .  . 
The  caterpillars  of  the  last  fall  generation  enter  the  ground  and  hib- 
ernate as  pupae.  The  insect  has  several  other  food-plants  aside 
from  cotton,  but  its  most  abundant  food  in  the  South  is  the  weed 

*  Chloridea  mrescens  Fab.,  and  C.  obsoleta  Fab.     Family  Noctuidoe. 
t  See  corn  ear-worms  for  full  description  and  illustrations, 
i  Farmers'  Bulletin  120,  U.  S.  Dept.  Agr.      The  principal  Insects  Affect- 
ing the  Tobacco  Plant. 


222       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


known  as  ground  cherry  (Phy salts  viscosa)."  The  life  history 
of  this  species  is  very  similar,  therefore,  to  the  false  budworm  or 
bollworm. 

The  corn  ear-worm  (which  see)  is  usually  found  attacking 
tobacco  in  Virginia  and  Kentucky  only  late  in  the  season  after 
corn  has  commenced  to  harden.  It  then  bores  into  the  buds,  seed- 
pods,  and  flower-stalks,  in  the  same  manner  as  the  last  species.  In 

Florida,  however,  Pro- 
fessor A.  L.  Quaintance 
states  that  its  worst  in- 
jury is  done  early  in  the 
season  before  corn  or  cot- 
ton are  available,  the 
eggs  being  laid  in  the  bud 
and  the  young  larvae  feed- 
ing  on  the  unfolded 
leaves,  doing  very  serious 
injury.  In  Florida  the 
corn  ear-worm  or  false 
budworm  is  more  com- 
mon than  the  former 
species. 

Control. — P  o  i  s  o  n  e  d 
corn-m  e  a  1  has  been 
found  to  be  a  satisfactory 
remedy  for  both  species 
when  they  bore  into  the 
bud.     Mix  a  teaspoonful 

Fig.  187.-Larva  of  false  budworm  (Chloridea  ^^  ^^«^^^*^  of  lead  into  a 
obsoleta),  showing  work  on  seed  capsules  of  quart  of  finely  ground 
tobacco  plant.     (After  Quaintance.)  cornmeal   and     sprinkle 

into  the  buds  from  a  can  perforated  like  a  pepper  can.  This 
should  be  applied  frequently,  especially  after  heavy  rains. 
Large  buds  should  be  opened  and  a  pinch  of  the  poison  placed 
within.  When  spraying  or  dusting  with  an  arsenical  is  prac- 
ticed against  the  hornworms  it  will  aid  in  the  control  of  the  bud- 
worms,  and  may  be  advisable  for  them  alone  where  injury  is 
serious.     When  the  injury  by  the  false  budworm  occurs  only 


INSECTS  INJURIOUS  TO  TOBACCO 


223 


late  in  the  season,  it  would  seem  that  the  moths  might  be  attracted 
to  a  trap  crop  of  late  corn  in  the  same  manner  as  cotton  is  pro- 
tected from  it. 

The  Tobacco  Leaf-miner  * 

The  larva  of  a  small  moth  has  become  quite  injurious  in  part, 
of  North  Carolina  and  Florida  by  mining  the  inside  of  the  leafs 
and  is  thus  known  as  the  Tobacco  Leaf -miner.  This  insect  occurs 
in  other  parts  of  the  country,  but  has  become  injurious  only  in  the 
states  named  and  in  recent  years.  The  injury  is  done  by  the 
larvae  eating  out  irregular  patches  of  the  tissue  in  the  leaves,  leav- 
ing only    the  upper 


and  lower  surfaces, 
the  lower  leaves 
being  infested  the 
worst.  The  leaves 
are  rendered  u  n  fi  t 
for  wrappers,  split- 
ting and  tearing  very 
easily  on  account  of 
these  blotches.  A 
larva  does  not  con- 
fine its  work  to  one 
place,  but  makes 
several  mines,  and  a 
single  larva  may  thus  destroy  the  value  of  a  leaf  for  wrapping  pur- 
poses. This  migratory  habit  is  of  considerable  importance,  as 
in  leaving  the  old  and  in  making  new  mines  the  larvae  must 
necessarily  eat  a  certain  amount  of  the  surface  of  the  leaf,  and 
can  thus  be  killed  by  an  arsenical  spray.  The  life  history  of  th(? 
insect  is  not  completely  known,  but  as  only  about  twenty  days 
are  required  for  all  its  transformations,  several  broods  probably 
occur  during  a  season.  The  original  food-plant  of  this  pest  has 
been  found  to  be  the  common  horse  or  bull-nettle  {Solanum 
carolinense),  which  fact  further  emphasizes  the  caution  already 
given,  to  keep  all  weeds  carefully  cut  down  around  the  tobacco- 
field,  especially  those  nearly  related  to  tobacco  botanically.  Many 
planters  destroy  the  larvae  by  smiply  crushing  them  with  the  hand, 
and  this  can  be  done  quite  rapidly,  and  if  done  before  the  mines 
become  numerous  should  be  sufficient  to  check  the  injury. 
*  Phthorinioea  operculella  Zell.     Family  Tineidoe. 


Fig.  188. — Tobacco  leaf-rr.iner  or  split-worm:  adult 
moth  above;  larva  below  at  right;  pupa  below  at 
left,  with  side  view  of  enlarged  anal  segment — 
all  enlarged     (After  Howard,  U.  S.  Dept.  Agr.) 


224       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Where  spraying  or  dusting  is  practised  against  the  hornworm 
it  should  be  sufficient  to  destroy  most  of  the  miners,  as,  if 
the  leaf  is  thoroughly  coated  with  poison,  they  would  get  a  fatal 
dose  in  starting  a  new  mine. 

The  Cigarette-beetle  * 

The  most  serious  pest  of  dried  tobacco  is  the  little  brown 
Cigarette-beetle,  which  also  attacks  various  drugs  and  stored 
food  products.  The  beetle  is  but  one- 
sixteenth  inch  long,  of  a  brownish  color,  and 
with  the  pro-thorax  bent  down  so  that  the 
head  is  obscured  as  if  under  a  hood. 

"Working  as  it  does  in  all  kinds  of  cured 
tobacco  and  living  in  this  substance  during 
all  the  stages  of  its  existence,"  says  Dr. 
L.  0.  Howard,  "it  damages  cigarettes  and 
cigars  principally  by  boring  out  of  them, 
making  round  holes  in  the  wrappers  so  that 
they  will  not  draw.  Leaf  tobacco  is  injured 
for  wrapping  purposes  by  being  punctured 
with  holes  made  both  by  the  larvae  and 
beetles,  and  fillers  and  finecut  are  injured 
by  the  reduction  of  their  substance  by  the 
actual  amount  consumed  by  the  larvae." 
"  The  cigarette-beetle  is  practically  cosmo- 
politan, and  probably  occurs  in  most  tobacco 
factories  in  the  Southern  States,  as  well  as 
in  most  wholesale  drug  stores.  In  the  far 
South  this  insect  multiplies  rapidly  through- 
out the  greater  part  of  the  year,  and  its 
development  is  practically  continuous  in 
artificially  warmed  factories  farther  north." 
Life  History. — In  heated  factories  the  in- 
sect may  be  found  in  all  stages  throughout 
the  year.  Otherwise  it  seems  to  pass  the 
winter  months  in  the  larval  state.  The 
larva  is  slightly  larger  than  the  beetle  and 
covered  with  hair  as  shown  in  Fig.  190. 
When  full  grown  it  spins  a  compact  silky 

*  Lnsioderma  serricorne  Fab.     Family  Ptinidoe. 


Fig.  189.— Work  of 
split-worm  reduced. 
(After  Howard,  U.  S. 
Dept.  Agr.) 


INSECTS  INJURIOUS  TO  TOBACCO 


225 


cocoon  covered  with  bits  of  whatever  it  is  breeding  in  and  in  it 
transforms  to  the  pupa.  In  a  warm  room  the  entire  life  cycle  has 
been  passed  in  forty-seven  days,  and  it  seems  probable  that  in 
the  District  of  Columbia,  there  are  two  generations  a  year.  The 
life  is  undoubtedly  intimately  related  to  the  moisture  and  temp- 
erature conditions  under  which  it  lives. 

Control. — When  a  factory  or  storehouse  has  become  badly 
infested  a  thorough  cleaning  is  the  first  step  in  the  control  of 
the  pest,  as  tobacco  fragments  and  dust  are  usually  present  every- 


CL  b  &  d' 

Fig.  190. — The  cigarette  beetle:  a,  larva;  h,  pupa;  c,  adult;  d,  side  viw  of 
adult;  e,  antenna— all  greatly  enlarged;  e,  stiU  more  enlarged.  (After 
Chittenden,  U.  S.  Dept.  Agr.) 

where  and  ideal  conditions  for  the  multiplication  of  the  pest  are 
afforded. 

Infested  tobacco  should  be  opened  up,  if  packed  tightly, 
placed  in  tight  boxes  or  in  a  tight  room  and  exposed  to  the  fumes 
of  carbon  bisulfide,  using  it  the  same  as  for  grain  insects. 

The  quantity  used  will  depend  upon  the  tightness  of  the 
enclosure,  the  way  in  which  the  tobacco  is  packed,  and  the  tem- 
perature. One  pound  to  every  200  cubic  feet  will  usually  be  ample. 
In  factories  where  the  beetle  is  abundant  the  tobacco  should  be 
steamed  before  use,  which  will  kill  all  stages  of  the  insect.  Loose 
tobacco,  cigars,  and  cigarettes,  should  not  be  left  exposed  to  the 
beetles,  but  should  be  covered  up  or  placed  in  tight  receptacles 
to  prevent  their  access.  Badly  infested  factories  and  storehouses 
may  be  fumigated  with  hydrocyanic  acid  gas.  Heating  would 
be  effective  where  practical. 

Several  other  insects  are  more  or  less  serious  pests  of  tobacco 

in  certain  parts  of  the  country  or  under  local  conditions.     The 

Tobacco   Thrips*   has    caused    considerable   loss    to    growers   of 

wrapper  tobacco  in  Florida  where  it  is  grown  under  shade. 

*  Euthrips  nicotaniae  Hinds.  Order  Thysanoptera.  See  W.  A.  Hooker, 
Bulletin  65,  and  Circular  68,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


CHAPTER  XIII 
INSECTS  INJURIOUS  TO  COTTON  * 

Plant-lice  f 

With  the  formation  of  the  first  true  leaves  of  cotton,  winged 
aphids  or  plant-lice  appear  in  large  numbers  on  the  under  side 
and  on  the  terminals,  the  "buds  "of  the  plants  often  being  black 
with  them.  Almost  all  of  them  are  the  common  greenish  Melon- 
aphisl  (see  page  344),  which  infests  melons  later  in  the  season. 
It  is  evident,  therefore,  that  the  practice  of  planting  cotton 
between  rows  of  melons  is  undesirable.  The  aphids  migrate 
to  the  cotton  while  it  is  young  from  various  common  weeds  upon 
which  they  have  passed  the  winter. 

Another  species,  known  as  the  Bur-clover  Aphis  §  occurs  on 
cotton  at  about  the  same  time  and  is  not  readily  distinguishable 
from  the  previous  species,  but  is  darker  and  has  a  shining  reddish 
or  brownish-black  color. 

In  cold  weather  these  plant-lice  often  cause  considerable 
injury  to  the  young  plants,  and  greatly  retard  their  development, 
since  they  multiply  very  rapidly  and  feed  mostly  on  the  growing 
terminals.  If  there  be  a  few  warm  days,  however,  hordes  of 
small  Hymenopterous  parasites  appear  and  in  a  few  days  often 
completely  rid  the  plants  of  the  pest. 

Control. — Although  these  aphids  may  be  destroyed  by  spray- 
ing with  kerosene  emulsion,  whale-oil  soap,  or  tobacco  water, 
as  a  rule  the  use  of  these  on  any  considerable  scale  will  hardly  be 
profitable.  Keeping  the  fields  clear  of  weeds  by  faU  and  winter 
plowing  will  undoubtedly  have  a  beneficial  effect  in  reducing 

*  See  Hunter  and  Hinds,  The  Mexican  Cotton  Boll  Weevil,  Bulletin  51, 
Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  Quaintance  and  Brues,  The  Cotton 
Bollworm,  Bulletin  50,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  Sanderson, 
Miscellaneous  Cotton  Insects  of  Texas,  Bulletin  57,  Bureau  of  Entomology, 
Farmers'  Bulletin  223,  U.  S.  Dept.  Agr. 

t  Family  Aphididce. 

X  Aphis  gossypii  Glov. 

§  Aphis  medicaginis  Koch. 

226 


Fig.  191. — The  cotton  worm  {Alabama  argillacea):  young  and  full-grown 
larvaj  or  worms,  pupa,  cocoons  in  folded  leaves,  and  moths,  at  rest,  and 
with  wings  expanded — three-fourths  natural  size.     (After  Comstock.) 

227 


228        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

the  numbers  of  aphids  and  in  most  cases  will  be  the  only  treat- 
ment necessary. 

The  corn  root-aphis  is  also  recognized  as  a  pest  of  cotton, 
especially  the  young  plants.  When  it  appears  it  may  be 
controlled  to  some  extent  by  frequent  shallow  cultivation  of  the 
young  plants  until  they  are  well  established.  Infestation  may  be 
avoided  by  a  system  of  rotation  where  cotton  does  not  follow 
either  cotton  or  corn  in  infested  fields.* 

The  Cotton  Worm  f 

Until  the  advent  of  the  boll  weevil,  the  cotton  worm  was 
much  the  most  serious  insect  pest  of  cotton.     Since  then,  however, 


Fig.  192. — Pimpla  conquisitor,  one  of  the  principal  parasites  of  the  cotton- 
caterpillar:  a,  larvae  enlarged;  b,  head  of  same  still  more  enlarged;  c,  pupa; 
d,  adult  female  enlarged;  e,  f,  end  of  abdomen  of  adult  male,  still  more 
enlarged.     (From  Fourth  Rept.  U.  S.  Entom.  Comm.)  1 

its  importance  has  been  rather  overshadowed  in  the  mind  of  the 

planter  by  the  onslaught  of  the  invading  Mexican  pest  and  where 

the  boll  weevil  is  abundant  the  stripping  of  the  late  foliage  by 

the  cotton  worm  really  aids  in  the  control  of  the  weevil,  as  will 

be  explained  later. 

Life  History. — During   the    winter   months    the    adult    moth 

hibernates  in  the  most  southern  portion  of  the  cotton-belt,  in  the 

rank  wire-grass  occurring  in  the  more  thickly  timbered  regions. 

*  See  W.  A.  Thomas,  S.  C.  Expt.  Sta.  Bulletin  175. 

t  Alabama  argillacea  Hubn.     Family  Noctuidce.      See  W.  E.  Hinds,  Bul- 
letin 164,  Alabama  Agr.  Expt.  Station. 


INSECTS  INJURIOUS  TO  COTTON 


229 


Only  a  few  of  these  survive,  but  they  are  very  capable  ancestors.  In 
early  March  they  lay  eggs  upon  volunteer  cotton  when  it  is  only 
an  inch  or  two  high.  The  eggs  are  laid  singly,  usually  upon  the 
under  surface  of  the  leaves  near  the  top  of  the  plant,  and  about 
500  are  laid  by  each  female.  The  egg  is  of  a  flattened  convex 
shape,  bluigh-green  in  color,  and  with  prominent  ridges  converging 
to  the  apex.  In  midsummer  the  eggs  hatch  in  three  or  four  days, 
but  in  spring  and  autumn  a  much  longer  time  is  required.  The 
young  larvae  are  a  pale  yellow  color,  but  soon  assume  a  greenish 
tinge,  and  are  marked  with  dark  spots  which  become  more  dis- 
tinct after  the  first  moult,  when  they  become  marked  like  the  full- 
grown  caterpillars,  being 
more  or  less  striped  with 
black.  During  the  early 
season  the  greenish  cater- 
pillars predominate,  but 
later  the  black  stripes 
become  heavier  and  the 
darker  forms  prevail. 
The  appetites  of  these 
caterpillars  are  only  too 
well  known  to  the  cotton- 
grower.  At  first  they  are 
content  with  eating  only 
the  under  surfaces  of  the 
leaves,  occasionally  pierc- 
ing through.  Then  the 
leaves  commence  to  look 
ragged,  and  when  they 
become  scarce  the  tender  twigs  and  buds  are  attacked.  When 
they  are  excessively  abundant  the  larvae  develop  cannibalistic 
tendencies,  like  the  boll  worms,  and  often  feed  upon  the  weaker 
caterpillars.  The  larvae  become  full  grown  in  from  one  to  three 
weeks,  during  which  time  they  moult  some  five  times. 

When  mature  the  caterpillar  crawls  into  a  folded  leaf,  which  is 
often  so  eaten  away  that  the  pupa  hangs  exposed,  and  there 
spins  around  it  a  thin  silken  cocoon  and  transforms  to  the  pupa, 
in  -which  state  the  insect  remains  dormant  for  from  one  to  four 
weeks,  when  it  emerges  as  an  adult  moth. 


Fig.  193. — Cotton-worm  egg  parasite  (Pentar- 
thron  minutem):  a,  adult  female,  greatly 
enlarged;  b,  ovipositor;  c,  female  antenna; 
d,  male  antenna.  (From  Fourth  Rept.  U.  S. 
Entom.  Comm.) 


230         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  moth  is  a  dull  olive-gray  color  with  a  wing  expanse  of 
about  1^  inches,  which  sometimes  have  a  purplish  lustre,  and  which 
are  marked  with  darker  lines  as  shown  in  Fig.  191.  Like  most  of 
the  owlet  moths  it  flies  only  after  sunset,  but  unlike  them,  it  is 
not  confined  to  the  nectar  of  flowers  for  food,  as  its  mouth  is 
peculiarly  adapted  to  piercing  the  skin  of  ripe  fruit  and  feeding 
upon  its  juices.  Injury  by  the  cotton  worm  moth  to  ripened 
peaches  is  frequently  noticed  in  the  peach  orchards  of  West 
Virginia  and  regions  farther  north.  The  moths  are  strong  fliers, 
those  of  the  later  broods  being  frequently  found  as  far  north  as 
Canada. 

The  first  two  generations  develop  rapidly  and  in  the  extreme 
South  the  moths  emerge  by  early  April  and  are  carried  north- 
ward by  the  prevailing  winds.  Eggs  deposited  by  them  give 
rise  to  a  brood  of  moths  which  in  turn  fly  farther  northward, 
and  thus  the  worms  are  gradually  found  throughout  the  whole 
cotton  belt,  though  with  a  considerable  confusion  between  the 
various  generations.  At  least  seven  generations  occur  on 
the  Gulf  Coast,  and  three  at  the  northern  limit  of  the  species. 
Considering  the  number  of  eggs  laid  by  each  female  and 
this  number  of  generations,  it  may  be  readily  perceived  how 
such  immense  numbers  of  the  caterpillars  may  arise  by  the  latter 
part  of  the  season,  in  a  region  where  practically  none  remain 
over  winter.  If  none  was  killed,  the  progeny  of  a  single  moth 
after  four  generations  would  amount  to  over  300,000,000,000 
individuals,  or  if  placed  end  to  end,  the  third  generation  would 
be  enough  to  encircle  the  earth  at  the  equator  over  four  times. 

Enemies. — It  is  thus  very  fortunate  that  there  are  many 
deadly  enemies  of  the  cotton  worms,  which  commence  their  war- 
fare upon  them  with  their  first  appearance  in  spring  and  continue 
it  with  increasing  ardor  throughout  the  season.  One  of  the  most 
effective  of  these  is  a  minute  little  insect,  Trichogramma  pretiosa, 
which  develops  within  the  eggs.  Mr.  H.  G.  Hubbard  once 
observed  that  in  Florida  from  75  to  90  per  cent  of  the  fourth 
brood  of  eggs  were  destroyed  by  this  parasite,  while  only  three 
or  four  eggs  in  a  hundred  escaped  in  the  sixth  brood.  Another 
of  the  most  useful  parasites,  Pimpla  conquisitor,  was  noticed  as 
early  as  1847  to  destroy  nearly  all  of  the  pupae  of  the  last  brood. 
The  eggs  of  the  Pimpla  are  laid  upon  the  caterpillar,  and  the 


INSECTS  INJURIOUS  TO  COTTON  231 

maggots  enter  the  worm  and  feed  upon  its  juices.  It  changes 
to  a  pupa  as  usual,  but  the  pupa  soon  dies,  and  large  numbers 
are  thus  killed.  Several  similar  parasites  prey  upon  the  cotton 
worm,  and  it  is  to  be  regretted  that  we  know  of  no  way  of  encourag- 
ing their  valuable  work.  The  common  insectivorous  birds  eat 
large  numbers  of  the  worms,  especially  when  they  are  scarce 
in  early  spring,  and  they  should  be  protected  by  enacting  and 
•enforcing  most  stringent  laws  against  their  wanton  destruction. 

Control. — The  most  commonly  used  and  effective  remedy  is 
to  dust  the  plants  with  arsenate  of  lead.  Dusting  machines  drawn 
by  a  team  which  will  cover  four  rows  at  once  are  in  common  use. 
The  dust  may  be  applied  with  any  of  the  powder  guns,  but  it  is 
most  commonly  applied  to  two  rows  at  once  by  means  of  bags 
fastened  at  the  ends  of  a  pole  and  carried  by  a  man  on  horseback, 
who  can  thus  dust  15  to  20  acres  per  day.  These  sacks  are  about 
10  inches  long  by  4  inches  in  diameter,  open  the  whole  length 
on  one  side  and  firmly  sewed  at  the  ends.  Eight-ounce  Osnaburg 
is  the  best  cloth  for  the  purpose.  A  strip  of  oak  or  strong  wood 
about  1^x2  inches,  and  5  feet  long,  has  a  1-inch  hole  bored 
through  it  5  inches  from  each  end,  and  to  this  the  sack  is  tacked, 
fastening  one  of  the  edges  of  the  opening  to  each  of  the  narrow 
sides  of  the  pole.  The  sacks  are  filled  through  the  holes  in  the  pole. 
When  freshly  filled  a  sHght  jarring  will  shake  out  a  sufficient 
amount  of  the  poison,  but  when  nearly  empty  the  pole  should 
be  frequently  and  sharply  struck  with  a  short  stick  or  spaces 
will  be  missed.  The  poison  has  been  found  most  effective  with- 
out the  admixture  of  flour,  but  if  it  is  used,  lighter  cloth  should 
be  used  for  the  sacks. 

Besides  the  general  use  of  poisons  there  have  been  several 
important  factors  which  have  aided  in  the  control  of  the  cotton 
worm,  so  that  it  is  by  no  means  as  much  of  an  enemy  of  the  cotton 
crop  as  formerly.  Among  the  most  important  of  these,  both 
from  an  entomological  and  general  agricultural  standpoint,  is 
the  diversification  and  rotation  of  crops,  now  coming  to  be  more 
and  more  practiced  by  the  progressive  agriculturists  of  the  South, 
This  alone  largely  prevents  the  rapid  spread  of  the  pest.  Since 
the  seed  has  become  such  a  valuable  product  of  cotton,  smaller 
varieties  with  many  seeds  and  a  short  fibre  are  being  grown, 
in   contrast  to  the  rank-growing,   long-fibre  sorts  formerly  pre- 


232  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

ferred.     Thus  the  rows  are  more  open,  the  work  of  the  worms 
is  more  readily  detected  and  the  poison  more  easily  applied. 

Other  Caterpillars  Injuring  the  Foliage 

Several  of  our  common  caterpillars  which  ordinarily  feed  upon 
various  weeds  frequently  attack  cotton  foliage  in  restricted  local- 
ities and  do  more  or  less  serious  damage.  They  may  be  readily 
controlled  by  keeping  down  the  weeds  upon  which  they  normally 
feed  and  multiply  and  by  dusting  the  foliage  as  for  the  cotton 
worm  as  soon  as  they  are  noticed  upon  the  cotton  in  any  numbers. 

Among  the  more  common  of  these  leaf-eating  caterpillars 
is  the  Grarden  Web  worm*  (see  page  363),  which  may  be  recognized 
by  the  fine  silken  web  which  it  spins  over  the  young  plants. 
Another  is  the  White-lined  Sphinx  Caterpillar,!  a  yellowish- 
green  caterpillar  with  black  eye-spots  and  faint  stripes,  varying 
to  blackish  with  yellow  spots,  and  distinguishable  from  most 
other  cotton  caterpillars  by  the  horn,  characteristic  of  sphingid 
caterpillars,  at  the  tip  of  the  abdomen.  The  Salt-marsh  Cater- 
pillar |  which  is  one  of  our  best-known " woolly  bear"  caterpil- 
lars, covered  with  black  and  red  hairs,  has  frequently  stripped 
cotton  of  foliage  in  Texas,  as  does  the  Fall  Army  Worm  (see  page 
114),  when  it  becomes  locally  overabundant.  Many  other  species 
might  be  mentioned  which  do  more  or  less  local  injury. 

The  Cotton  Square-borer  § 

Just  as  the  cotton  squares  commence  to  form  they  are  often 

bored  into  by  a  small  green   caterpillar  which  many  planters 

consider  a  stage  of  the   bollworm  and  which  others  have  called 

the   "sharpshooter."    This   injury  is   often   quite   serious   on   a 

small  area,  as  we  have  seen  10  per  cent  of  the  stalks  entirely 

denuded  of  squares  in  small  fields  in  Texas  where  this  insect  was 

abundant.     The  little  caterpillars  hollow  out  the  squares  in  the 

same  manner  as  does  the  bollworm,  often  destroying  all  of  those 

on  a  plant  knee-high  and  even  boring  into  the  tender  stalk.     The 

caterpillars  are  bright   green,  oval,  decidedly  flattened,  covered 

with  short  hairs  which  give  them  a  velvety  appearance,  and  with 

*  Loxostege  similalis  Guen.     Family  Pyralidce. 
t  Deilephila  lineata  Fab.     Family  Sphingidce. 
t  Estigmene  acrcea  Drury.     Family  ArctiidcB. 
§  Uranotes  melinus  Hbn.     Family  Lyccenidoe. 


INSECTS  INJURIOUS  *T0  COTTON 


233 


the  head  retracted  under  the  front  of  the  body,  thus  being  quite 
unhke  any  stage  of  the  bolhvorm.  They  are  the  larvae  of  a  dainty 
Httle  butterfly  (Fig.  194), 
of  a  bluish-black  color, 
with  dark  reddish  lustre, 
and  with  bright  red  spots 
on  the  posterior  border 
of  the  hind  wings,  com- 
mon around  cotton-fields. 
The  small  yellowish, 
transparent  eggs  are  laid 
on  the  leaves  and  stems 
of  cotton,  cow-peas,  goat- 
weed,  and  various  weeds, 
and  the  larvse  have  also 


Fig.  194. — The  cotton  square-borer  {Uranotes 
melinus  Hbn.):  a,  aclult;  6,  underwing  of 
same ;  c,  larva ;  d,  pupa — natural  size.  (After 
Howard,  U.  S.  Dept.  Agr.) 


been  found  on  hops,  beans  and  cow-peas,  seeming  to  prefer  the 
latter  to  cotton.  The  eggs  hatch  in  from  two  to  five  days,  the 
larvae  become  grown  in  a  little  over  two  weeks,  and  the  pupal 

stage  averages  about 
ten  days,  so  that  the 
whole  life  cycle  re- 
quires about  a  month 
in  Central  Texas, 
where  there  are  three 
or  four  generations  in 
a  season. 

Fortunately  for  the 
planter  the  large  ma- 
jority of  the  caterpil- 
lars are  parasitized, 
over  90  per  cent  of 
the  June  generation 
having  been  thus 
destroyed. 

Usually,  therefore, 
it  is  hardly  worth  while 
to  attempt  to  combat 
this  insect,  as  it  is  not 


Fig.  195. — The  glassy-winged  sharpshooter  {Ho- 
malodisa  triqiietra  Fab.) :  adult  at  left,  last 
stage  of  nymph  at  right,  young  nymph  below 
— all  enlarged.  (Author's  illustration,  U.  S. 
Dept.  Agr.) 


234 


INSECT  PESTS  OF 'FARM,  GARDEN  AND  ORCHARD 


often  seriously  injurious  year  after  year.  Should  remedial  treat- 
ment be  necessary,  thorough  dusting  with  Paris  green  or  arsenate 
of  lead  would  probably  destroy  most  of  them,  as  the  young  cater- 
pillars, like  the  bollworms,  feed  to  some  extent  upon  the  foliage 
before  entering  the  squares. 

"  Sharpshooters  "  or  Leafhoppers  * 

In  late  summer  reports  are  frequent  that  cotton  is  being 
injured  by  "sharpshooters,"  especially  on  low  land.  These  insects 
are  reported  to  puncture  the  squares  and  bolls,  causing  them  to 


Fig.     196. — Three     cotton 
/K^ a,  Aulacizes  irrorata-%,  Oncometopia  undatath,  Oncometopia  lateralis — 
much  enlarged.     (Author's  illustration,  U.  S.  Dept.  Agr.) 

drop  prematurely^  a  small  black  speck  showing  the  spot  where 
punctured.  The  insect  which  has  been  most  commonly  credited 
with  this  work  is  the  Glassy-winged  Sharpshooter,  f  but  with  it  are 
usually  associated  several  near  relatives  with  similar  habits.|  Few 
planters  are  able  to  identify  the  cause  of  the  supposed  injury,  but 
many  know  these  insects  as  "dodgers,"  from  their  habit  of  quickly 
dodging  to  the  opposite  side  of  the  stem  when  disturbed.  Ex- 
tensive obserA^ations  and  repeated  experiments  during  two  seasons 

*  Family  Jassidce.  0  t  Homalodisca  triquetra  Fab. 

t  Oncometopia  undata  Fab.,  O.  lateralis  Fab.,  and  Aulacizes  irrorata  Fab. 


INSECTS  INJURIOUS  TO  COTTON 


235 


failed  to  show  the  sUghtest  evidence  that  these  insects  are  ever  in- 
jurious to  cotton,  though  they  are  common  upon  it,  the  supposed 
injury  being  undoubtedly  due  to  the  physiological  condition  of  the 
plant  which  causes  a  shedding  of  the  fruit  at  the  season  when 
the  supposed  injury  occurs. 

The  adult  insects  hibernate  in  rubbish  on  the  ground  near  the 
food-plants  and  appear  in  early  spring  on  the  elm,  hackberry,  red- 
bud,  Cottonwood,  willow,  and  the  tender  shoots  of  other  trees, 
especially  on  bottom-land  near  streams.  Here  they  suck  the 
juices  of  the  tender  leaves  and  deposit  their  eggs  in  them.  The 
eggs  are  laid  in  rows  of  ten  to  fifteen,  side  by  side,  just  under  the 


Fig.  197. — The  cotton  leaf-bug  (Calocoris  rapidus):  a,  adult;  h,  c,  d,  stages  in 
growth  of  nymph;  and  cotton  boll,  showing  spots  injured  by  cotton  leaf- 
bug  all  enlarged.     (Author's  illustration,  U.  S.  Dept.  Agr.) 

surface  of  the  leaf,  forming  a  blister-like  mark.  They  hatch  in  a 
few  days  and  the  young  bugs,  or  njaiiphs,  are  grayish  or  yellowish 
in  color  and  resemble  the  adults  except  in  the  lack  of  wings.  Two 
or  three  generations  occur  annually  in  Texas,  and  the  insects  are 
not  common  on  cotton  until  midsummer.  The}^  are  exceedingly 
fond  of  banana  trees,  sorghum  and  sunflowers,  sometimes  doing 
considerable  injury  to  the  latter,  but  there  is  no  evidence  for  con- 
sidering them  pests  of  cotton. 

The  Cotton  Leaf-bug  * 

This  insect  was  the  cause  of  considerable  damage  in  Northern 
Texas  in  the  latter  part  of  the  season  of  1904,  and  had  been  pre- 

*  Calocoris  rapidus  Say.     Family  CapsidcB. 


236 


INSECT  PESTS  OF  FARM, -GARDEN  AND  ORCHARD 


viously  reported  as  a  pest  of  cotton,  though  its  injury  had  never 
been  general.  It  punctures  the  squares  and  bolls,  either  causing 
them  to  drop  or  making  the  bolls  shrivel  or  decay  when  punctured. 
The  feeding  punctures  in  the  bolls  are  indicated  by  small  black 
spots,  resembling  diseased  places,  which  gradually  become  larger 
and  sunken,  evidently  due  to  some  poisonous  substance  intro- 
duced by  the  beak  of  the  insect  as  it  sucks  the  juices  of  the  boll. 
The  bugs  may  be  readily  recognized  from  Fig.  197,  and  by  the 
bright  red  spots  just  beyond  the  middle  of  the  wing.  The  young 
are  light  green  marked  with  red.  Several  generations  of  the  insect 
occur  annually,  but  its  life  history  and  habits  are  still  unknown, 
and  no  means  of  combating  it  have  been  devised. 

Other  Plant-bugs  * 

Several   other   species   of   plant-bugs   do   considerable  injury 
by  sucking   the   bolls   and    causing   them   to   shrink    or   decay. 


Fig.  198. — The  green  soldier-bug  (Nezara  hilaris):  a,  adult;  h,  beak;  c,  eggs. 
d,  end  of  egg  more  enlarged;  e,  young  nymph;  /,  last  stage  of  nymph. 
(After  Chittenden,  U.  S.  Dept.  Agr.) 

Among  these  are  the  so-called  "pumpkin-bugs"  or  "stink-bugs," 
of  which  a  large  green  species f  is  the  most  commonly  injurious, 
while  the  blackish,  leaf-footed  plant-bugs,  |  which  are  more  abun- 
dant on  cucurbs,  do  similar  injury. 

*  See  A.  W.  Morrill,  Plant-bugs  Injurious  to  Cotton  Bolls.     Bulletin  86, 
Bureau  of  Entomology,  U.  S.  Dept.  Agr. 

t  Nezura  hilaris  Say.     Family  Pentatomidoe. 
X  Leptoglossus  oppositus  Say.     Family  Coreidoe. 


INSECTS  INJURIOUS  TO  COTTON 


237 


"  Cotton-stainer  "  * 

The  cotton-stainer  or  red-bug  is  stated  by  Hunter  to  be  the 
most  important  cotton  pest  in  Florida.  It  occurs  in  small  num- 
bers in  Georgia,  South  Carolina  and  Alabama,  but  does  practically 
no  injury  there.  The  principal  damage  is  due  to  the  bugs  punctur- 
ing the  bolls  in  feeding  and  staining  the  lint  a  brownish  color. 
This  stain  seems  to  arise  from  the  injured  seed,  at  least  it  is  most 
noticeable  around  the  seed.  The  cocklebur  seems  to  be  the 
most  important  of  the  native  food-plants,  though  the  bugs  feed 
on  the  night-shade  and  Hibiscus  and  sometimes  attack  oranges. 


Fig.   199. — The  red  bug,   or  cotton-stainer   (Dysdercus  suturellus)  enlarged, 
a,  nymph;  6,  adult.     (From  "  Insect  Life.") 

Prevention  of  the  growth  of  these  weeds  is  therefore  of  importance. 

As  the  bugs  usually  assemble  in  colonies,  their  red  color  may  be 

easily  observed  and  they  may  be  jarred  from  the  foliage  into 

buckets  containing  water  covered  with  a  film  of  kerosene.     In 

the  fall  and  winter  these  insects  assemble  in  numbers  on  piles 

of  cotton  seed,  which  may  thus  be  used  as  traps  and  the  bugs 

killed  with  kerosene  or  hot  water. 

*  Dysdercus  suturellus  H.  Schf.     Family  Pyrrhocoridce .     See  W.  D.  Hunter, 
Circular  149,  Bureau  of  Entomology,  U.  S.  Department  of  Agriculture. 


238  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Cotton  BoUworm  * 

One  of  the  most  destructive  and  widespread  pests  of  cotton  is 
the  boll  worm,  the  same  insect  as  the  ear  worm  of  corn  already- 
described,  which  should  be  consulted  for  the  life  history 
and  description.  Throughout  the  cotton  belt  the  moths  of  the 
third  generation  appear  about  August  1st.     At  that  time  the  ears 

of  corn  have  become  too 
hard  to  furnish  suitable 
food  for  the  larvae  and 
the  moths  therefore  lay 
their  eggs  on  the  cot- 
ton leaves,  though  if 
any  late  corn  is  in  silk 
it  is  decidedly  preferred. 
Thus  during  the  month 
of  August  the  cotton  is 
often  seriously  injured 
by  the  caterpillars  bor- 
ing into  the  bolls,  this 
injury  being  most  seri- 
ous in  recent  years  west 
of  the  Mississippi  and 
particularly  in  north 
Texas  and  Louisiana. 
The  total  damage  to  cot- 
ton is  estimated  at  upward  of  $40,000,000  per  annum.  Though 
more  or  less  damage  is  done  by  the  fourth  generation  of  worms, 
injury  is  rarely  serious,  as  the  numbers  are  greatly  "reduced 
by  parasites  and  unfavorable  weather  conditions. 

About  tworthirds  of  the  eggs  on  corn  are  parasitized  by  a 
tiny  little  insect  hardly  visible  to  the  naked  eye,t  which  be- 
comes so  abundant  late  in  the  season  as  effectively  to  check 
the  increase  of  the  pest. 

Wasps  are  effective  enemies  of  the  bollworms,  provisioning 
their  nests  with  them.     Several  species  of  tachina-flies  parasitize 

*  Chloridea  obsoleta  Fab.  Family  NoctuidoB.  See  Farmers'  Bulletin 
No.  290,  U.  S.  Dept.  Agr.,  by  F.  C.  Bishop  and  C.  R.  Jones  and  Bulletin  50, 
Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  by  A.  L.  Quaintance  and  C.  T. 
Brues. 

f  Trichogramma  pretiosa  Riley. 


Fig.  200. — BoUworm  at  work  on  cotton  bolls, 
boring  into  grown  boll — slightly  reduced. 
(After  Quaintance  and  Brues,  U.S.  Dept.  Agr.) 


INSECTS  INJURIOUS  TO  COTTON 


239 


the  caterpillars,  while  not  a  few  arc  killed  by  a  bacterial  disease. 
One  of  the  most  important  natural  factors  in  reducing  their  num- 
bers, however,  is  their  own  tendency  to  cannibalism,  the  larger 
caterpillars  attacking  and  destroying  the  weaker  with  a  consequent 
marked  reduction  in  numbers. 

Control. — As  in  protecting  corn  from  this  pest,  the  most  effect- 
ive means  is  the  plowing  of  the  land  containing  the  pupae  in  winter 
or  late  fall. 

Early  planting  of  early  fruiting  varieties  of  cotton,  with  a 

liberal  use  of  fertilizers,  and  frequent  cultivation,  so  as  to  hasten 

the  maturity  of  the  crop,  will  result  in        ^?^ 

a  good  crop  being  made  before  the 

worst  injury  by  the  boll  worm  occurs. 

These  cultural  measures  ensure  the  best        "^'^-^ 

crops  even  where  there  are  no  insects    Fig.  201. —Egg  of  bollworm; 

.  side  and  top  views.     Highly 

to  be  avoided,  and  as  an  early  crop       magnified  (From  Quaintance 

is  less  injured  by  almost  all  cotton       """"^  2^"^'^'  U-  S.  Dept.  Agr.) 

insects,  the  planter  should  adjust  his  methods  to  secure  earliness. 

As  the  eggs  are  laid  mostly  on  the  cotton  leaves  and  the  little 


Fig.  202. — Bolhvorms  showing  variation  in  color,  upper  larva  green,  middle 
rose,  and  lower,  dark  brown — twice  natural  size.  (After  Quaintance  and 
Brues,  U.  S.  Dept.  Agr.) 

caterpillars  nibble  the  surface  before  boring  into  the  bolls,  the 
poisoning  of  the  foliage  when  the  eggs  are  hatching  will  result  in 
a  very  material  reduction  of  the  subsequent  injury.     Paris  green 


240  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


has  been  most  generally  used,  but  recently  powdered  arsenate  of 
lead  has  been  found  superior  to  it.  Arsenate  of  lead  is  used  at  the 
rate  of  2  to  5  pounds  per  acre,  applied  either  pure  or  diluted  with 
lime  or  flour,  using  either  a  bag  and  pole,  hand  powder-gun  or  geared 
dusting  machine.  The  dusting  should  be  done  while  the  plants 
are  wet  with  dew.  When  not  followed  immediately  by  rain,  two 
applications  should  be  sufficient,  the  first  when  the  eggs  commence 


"*"'^ 


?'M'^!!^BB^'?.'5 


Fig.  20:;.  -Pupa  nf  the  hnllworm  in  its  Imrrow  in  the  soil,  showing  burrow 
made  by  the  larva  and  filled  in,  and  the  exit  burrow  for  the  moth  also 
made  by  the  larva — natural  size.  (After  Quaintance  and  Brues,  U.  S. 
Dept.  Agr.) 

to  hatch  in  numbers,  usually  between  July  25th  and  August  5th, 
and  the  second  about  a  week  later.  If  rains  follow,  the  appHca- 
tions  should  be  at  once  repeated. 


INSECTS  INJURIOUS  TO  COTTON 


241 


Inasmuch  as  the  moths  prefer  to  lay  their  eggs  on  corn-silk, 
cotton  ma}^  be  very  effectively  protected  by  the  use  of  strips  of 
late  corn  and  cow-peas,  planted  through  the  cotton  so  as  to  act  as  a 
trap  crop.     Leave  vacant  strips  four  or  five  rods  wide  across  the 
fields  when  planting  cotton.     About  June  1st  plant  these  with 
alternate  rows  of  Mexican  June  corn  and  cow-peas.     This  will  bring 
the  corn  into  silk  about  the  first  of  August  and  will  attract  the 
moths  to  lay  their  eggs  upon  it  instead  of  the  cotton,  while  the 
cow-peas  will  furnish  both  food  and  shelter  to  the  moths.     Corn 
should  never  be  planted  with  cotton  when  cotton  is  planted,  for 
instead  of  acting  as  a  trap  crop  it  merely  furnishes  food  upon 
which    the    worms     - 
multiply  during  the 
earl}^     season     and 
forces   those   of  the 
third   generation  to 
the    cotton.        The 
strips    of    corn    and 
peas  should  be  cut 
as     soon     as    the 
worms  on  them  be- 
come    fairly    grown 
and  the  land  plowed 
to  destroy  any  which  may  have  pupated.    "  On  large  plantations  the 
planting  of  small  areas  of  corn  here  and  there  in  the  fields  is  prac- 
ticable.    Such  early  crops  as  potatoes,  oats,  or  wheat  may  be 
followed  by  corn  and  cow-peas  with  practically  the  same  results." 

The  Cotton-boll  Cutworm  * 

The  larva  of  this  species  is  a  very  common  feeder  upon  the 
foliage  of  cotton  and  late  in  the  season  bores  into  the  bolls  in 
much  the  same  manner  as  the  boll  worm.  Cotton  is  but  one 
of  a  long  list  of  food-plants,  however,  as  it  is  a  common  pest 
of  sugar-beets,  corn,  wheat,  cabbage,  potato,  asparagus,  salsify, 
peach,  raspberry,  violet,  cucumber,  tomato,  turnips,  pea,  rape, 
pigweed,  cottonwood,  and  grasses  according  to  Chittenden. 
It  occurs  commonly  throughout  the  states  east  of  the  Rocky 
Mountains. 

*  Prodenia  ornithogalli  Guen.  Family  Noctuidoe.  See  Sanderson,  I.e., 
and  F.  H.  Chittenden,  Bulletin  27,  n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr.,  p.  64. 


Fig.  204. — ^The  moth  of  the  bollworm  or  corn  ear- 
worm — enlarged  one-fourth.  (After  Quaintance 
and  Brues,  U.  S.  Dept.  Agr.) 


242         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  moth  has  a  wing  expanse  of  about  1|  inches,  the  fore- 
wings  being  a  dark,  rich,  velvety  brown,  marked  with  black, 
yellow  and  ochreous  as  shown  in  the  illustration,  while  the  hind- 
wings  are  a  hght  gray.  The  grown  caterpillar  is  1|  to  if  inches 
long,  and  is  quite  variable  in  coloration,  some  being  much  darker 
than  others,  as  shown  in  the  illustration.  The  three  whitish 
lines  and  the  double  row  of  triangular  brown  spots  along  the  back 
of  the  lighter  forms  will  easily  distinguish  this  caterpillar  from 
the  boll  worm.* 


Fig.  205. — The  cotton-boll  cutworm  {Prodenia  ornithogalli  Guen.):  dark 
form  of  male  moth  above;  pale  form,  female  moth  below;  a,  pale  form 
of  larva;  b,  dark  form  of  larva;  c,  lateral  view  of  abdominal  segments  of 
pale  form;  d,  same  of  dark  form.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

Life  History. — The  life  history  has  not  been  carefully  observed 
in  the  North,  but  from  observations  made  by  the  writer  in  Texas 
the  life  history  in  the  Gulf  States  seems  to  be  as  follows: 

The  winter  is  usually  passed  in  the  pupal  stage  in  the  soil, 
though  possibly  a  few  moths,  emerging  late,  hibernate.  The 
first  brood  of  moths  appears  from  the  middle  of  May  until  the 
middle  of  June,  mostly  early  in  June.  A  second  brood  apjDears 
during  the  latter  half  of  July,  and  a  third  late  in  August  and  dur- 
ing September.  A  few  of  the  fourth  brood  may  emerge  in  Decem- 
ber, but  most  of  them  do  not  do  so  until  the  very  early  spring, 
when  they  lay  eggs  upon  various  weeds  on  which  the  larvae  feed 

*  See  Chittenden,  I.e.,  p.  3G,  for  distinguishing  characters  of  related  species 
of  Prodenia. 


INSECTS  INJURIOUS  TO  COTTON  243 

until  cotton  appears.  The  length  of  time  occupied  in  the  dif- 
ferent stages  is  seen  to  be  quite  variable,  but  is  approximately 
six  days  for  the  egg,  twenty  days  for  the  larva,  and  thirteen  days 
(usually  ten  to  fifteen  days)  for  the  pupa — making  a  total  of 
about  forty  days  for  the  complete  life  cycle.  Dr.  Chittenden 
believes  that  there  are  two  generations  in  the  North  and  probably 
three  in  the  latitude  of  the  District  of  Columbia. 

Control. — This  species  has  not  been  sufficiently  injurious  on 
cotton  to  warrant  extensive  experiments  in  its  control.  Where 
it  attacks  young  plants  of  cotton  or  other  crops,  it  may  be  com- 
bated with  the  means  suggested  for  other  cutworms.  Where 
it  becomes  injurious  to  the  bolls,  it  might  be  controlled  by  thorough 
dusting  or  spraying  with  arsenicals,.  which  would  destroy  the 
young  larvae  while  they  are  still  feeding  on  the  foliage. 

The  Mexican  Cotton  Boll  Weevil  * 

Not  since  the  invasion  of  the  Mississippi  Valley  by  the  Rocky 
Mountain  locusts  in  the  70's  has  any  insect  caused  such  ruin 


Fig.  206. — The  cotton  boll  weevil,  natural  size,  showing  variation  in 
size  and  color. 

to  any  staple  crop  as  has  the  boll  weevil  in  the  territory  affected 

during  the  past  twenty  years,  and  it  is  one  of  the  factors  in  the 

recent  high  prices  of  cotton. 

Like  several  of  the  worst  insect  pests  of  the  South  it  is  a  native 

of  Central  America  and  came  to  us  from  Mexico,  crossing  the 

Rio  Grande  at  Brownsville,  Texas,  about  1890.     As  early  as  1862 

the  weevil  caused  the  growers  at  Monclova,  Mexico,  to  abandon 

cotton  culture  and  when  they  again  planted  it  in  1893,  the  beetle 

promptly  appeared  and  destroyed  the  entire  crop.     It  multiplied 

*  Anthonomus  grandis  Boh.  Family  Curculionidce.  See  W.  D.  Hunter. 
"The  Boll  Weevil  Problem,"  Farmers'  Bulletin  848,  U.  S.  Dept.  Agr.;  and 
Hunter  and  Hinds,  Bulletin  51,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


244  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


rapidly  in  south  Texas,  ruining  the  crops,  and  by  1895  had  spread 
northward  to  a  hne  extending  eastward  from  San  Antonio. 
Since  then  it  has  spread  northward  and  eastward,  about  sixty 
miles  a  year,  until  in  1905  it  had  covered  all  of  Texas  and  western 
Louisiana  and  is  now  found  almost  throughout  the  cotton  area 
where  weather  conditions  permit. 

In  1904,  after  an  exhaustive  study  of  all  available  data,  the 
writer    estimated  the  loss  in  Texas  alone   at   $25,000,000,   and 

that  the  pest  had  then  cost  the 
State  $100,000,000.  Owing  to 
decrease  in  acreage  and  the  gen- 
eral use  of  methods  for  preventing 
or  avoiding  injury,  the  injury 
has  not  increased  proportion- 
ately to  the  spread  of  the  pest, 
but  the  total  annual  loss  is  at 
least  as  much  as  in  1904,  though 
no  accurate  estimates  have  been 
recently  made  for  the  whole  ter- 
ritory affected 

Life  History. — The  parent  in- 
sect is  a  small  brownish  beetle  about  one-quarter  inch  long, 
varying  from  one-eighth  to  one-third,  including  the  snout,  which 
is  about  half  as  long  as  the  body.  Recently  emerged  weevils 
are  light  yellowish  in  color,  but  they  soon  become  grayish- 
brown  and  later  almost  blackish.  There  are  many  nearly  related 
weevils  which  very  closely  resemble  the  boll  weevil,  and  only  an 
entomoligist  can  identify  the  species  with  certainty,  but  the  two 
teeth  at  the  tip  of  the  femora  of  the  fore-legs  (Fig.  207),  are  the 
most  characteristic  structure  by  which  it  may  be  distinguished. 
The  boll  weevil  feeds  only  upon  cotton,  and  weevils  found  feeding 
on  other  plants  are  certainly  of  other  species. 

However,  there  has  recently  been  discovered  in  Arizona  an 
insect  which  very  closely  resembles  the  boll  weevil  and  which  has 
been  classed  by  authorities  as  merely  a  geographical  variety 
of  the  true  boll  weevil  and  named  Anthonomus  grandis  thurheriae, 
the  Arizona  wild  cotton  weevil,  which  feeds  on  a  wild  cotton 
{Thurheria   thespesioides)  found    growing    in    that    region.     This 


Fig.  207. — The  cotton  boll  weevil- 
enlarged. 


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246        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


would  make  it  seem  probable  that  the  true    boll  weevil   might 
feed  on  the  wild  cotton  plant  as  well  as  on  the  true  cotton. 

The  weevils  commence  to  emerge 
from  hibernation  soon  after  cotton 
is  up  and  continue  to  emerge  until 
the  cotton  commences  to  square 
freely.  During  the  spring  the 
beetles  feed  on  the  foliage,  partic- 
ularly in  the  tender  terminals,  and 
as  soon  as  squares  are  formed  the 
females  commence  to  lay  their 
eggs  in  them.  Each  female  lays 
an  average  of  about  140  eggs,  lay- 
FiG.  209.— Cotton  square  with  bracts  ing  four  or  five  a  day.  The  female 
opened  to  show  weevil  at  work  on       . 

the  bud,  which  shows  a  feeding  drills  a  small  cavity  in  the  square 
puncture.  g^j^^j  [^  ^^  deposits  a  small  oval 

white  egg,  which  hatches  in  about  three  days.     The  grub  feeds 
upon  the  embryo  flower,  which  usually  fails  to  develop,  and  the 


Fig.  210. — The  cotton  boll  weevil;  eggs  among  the  anthers  at  points  indi- 
cated by  arrows,  the  cross-section  at  the  right  showing  opening  through 
which  egg  was  deposited — greatly  enlarged. 

infested  square  generally  falls  to  the  ground.     In  from  seven  to 
twelve  days  the  larva  is  full  grown  and  changes  to  the  pupa, 


INSECTS  INJURIOUS  TO  COTTON 


247 


which  stage  lasts  from  three  to  five  days.  Thus  from  egg  to 
adult  requires  from  two  to  three  weeks,  though  climatic  conditions 
cause  considerable  variation  in  the  length  of  time.  The  larva  is  a 
footless,  white  grub,  with 
brown  head,  which  lies  curled 
uj)  in  the  square  as  shown 
in  Fig.  211,  where  the  soft 
white  pupa  is  also  found. 
The  adult  weevils  feed  en- 
tirely during  the  day.  Their 
length  of  life  depends  upon 
various  conditions,  but  in 
the  summer  season  the  maj- 
ority do  not  live  over  sixty  Fig.211.— The  cottonbollweevil,larvaand 
J  ,.,,..,  ,  pupa— enlarged, 

days,  while  durmg  the  cooler 

part  of  the  year  those  which  hibernate  live  five  or  six  months. 

Many  squares  are  destroyed  by  the   feeding   punctures   of   the 

weevils.     "The  males  feed  upon  the  squares  and  bolls  without 

moving  until  the  food  begins 
to  deteriorate.  The  females 
refi^ain  from  ovipositing  in 
squares  visited  by  other  fe- 
males. This  applies  through- 
out most  of  the  season,  but 
late  in  the  fall,  when  all  the 
fruit  has  become  infested, 
several  eggs  may  be  placed  in 
a  single  square  or  boll.  As 
many  as  fifteen  larvae  have 
been  found  in  a  boll.  The 
squares  are  greatly  preferred 
as  food  and  as  p  1  a  c  e  s  for  de- 
positing eggs.  As  long  as  a 
supply  of  squares  is  present 
the  bolls  are  not  damaged  to 
any  serious  extent.  The  bolls, 
therefore,  have  a  fair  chance 

Fig  212.— Cotton  squares  broken  open,  i^.  Hpvplnn  jk?  Inno-  n<  <?niiflrp<5 
showing  the  boll  weevil  larvae  within  ^°  aeveiop  as  long  as  squares 
enlarged.  are  being  formed.     When- 


\ 


248        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

ever  frost  or  other  unfavorable  weather  causes  the  plants  to  cease 
putting  on  squares,  the  weevils  attack  the  bolls.  A  conservative 
estimate  of  the  possible  progeny  of  a  single  pair  of  weevils  during  a 
season  beginning  on  June  20,  and  extending  to  November  4,  is 
12,755,100."  —  Hunter.  Although  the  weevil  may  develop  from 
egg  to  adult  in  two  or  three  weeks,  it  requires  an  average  of  about 
forty-three  days  for  a  complete  generation  and  there  are  probably 
not  over  four  or  five  generations  in  a  season 

With  the  first  killing  frosts,  most  of  the  immature  stages 
developing  are  killed,  though  in  south  Texas  they  often  develop 

during  the  winter,  and  the  adult 
weevils  soon  go  into  hibernation. 
When  seeking  places  for  hiber- 
nation the  weevils  migrate  from 
field  to  field,  and  it  is  at  this 
t-!^-^  season  that  the  principal  migra- 
tion of  the  pest  takes  place.  The 
weevils  may  hibernate  in  hedges, 
woods,  corn-fields,  haystacks,  or 
farm  buildings,  particularly 
about  seed-houses  or  similar  sit- 
uations. Experiments  have 
shown  that  Spanish  moss  forms 
Fig  213.-Cotton  boll  weevils  hiber-  ^^  exceedingly  favorable  place 
nating  in  locks  or  cotton  removed  .  7  "^  ^ 

from  old  bolls  left  on  stalks  over   for  hibernation,  and  that  many 

'^*'^*®^-  weevils  pass  the  winter  in  it  on 

trees  some  distance  above  the  ground.  Others  may  hiber- 
nate in  the  cotton-field,  crawling  into  cracks,  under  grass, 
weeds,  and  trash,  and  in  the  empty  cotton  burrs,  while  in  the 
more  southern  sections  many  hil:)ernate  in  injured  bolls.  The 
weevils  which  hibernate  most  successfully  do  so  outside  of  the 
cotton  fields.  The  number  which  survive  the  winter  has  been 
accurately  determined  under  various  conditions  for  several  seasons, 
and  depends  upon  the  minimum  temperature,  the  amount  of  moist- 
ure, and  the  kind  of  shelter.  Thus  in  central  Texas  but  2  or  3  per 
cent  survive  in  many  normal  winters,  while  in  the  open  winter  of 
1906-07  11.5  per  cent  survived;  in  South  Texas  15  per  cent  may 
survive,  and  in  experiments  made  in  Central  Louisiana  in  1908-09 
with    rather  favorable    conditions    20    per  cent    survived.     The 


INSECTS  INJURIOUS  TO  COTTON 


249 


importance  of  reducing  the  number  which  survive  the  winter  is 
evident. 

Natural  Control—If  infested  squares  fall  to  the  ground  and  lie 
on  the  unshaded,  hot  soil  the  larvae  or  pup®  within  them  are  soon 
killed.  As  many  as  40  per  cent  of  the  immature  stages  have  thus 
been  found  dead  in  many  fields.  The  importance  of  wide  rows 
and  varieties  which  produce  little  shade  is  therefore  apparent,  and 
It  IS  evident  that  injury  will  be  much  less  on  dry  upland  soil,  and 
much  more  severe  in  bottoms  where  the  cotton  grows  rank  and 
thick. 

_  Over  a  score  of  parasites*  prey  upon  the  immature  stages 
withm  the  squares  or  bolls,  and  they  seem  to  be  increasing  in  num- 
bers and  effectiveness  as  they  become  adapted  to  living  upon  the 
weevil,  as  they  are  all  native  insects  which  prey  upon  nearly 


Fig.  214.-Chain  cultivator  for  use  in  drawing  weevil  infested  squares  to  center 

of  row.  (After  Hunter,  U.  S.  Dept.  Agr.) 
related  species  of  weevils  and  other  insects.  As  manv  as  two-thirds 
of  the  immature  stages  have  been  destroyed  by  them  in  certain 
helds,  though  ordinarily  not  ever  5  per  cent  of  the  total  are  para- 
sitized. Several  species  of  ants  also  feed  on  the  immature  stages 
20  to  30  per  cent  of  those  in  fallen  squares  and  bolls  often  being 
destroyed  by  them.  The  ants  destroy  manv  more  in  the  fallen 
squares  than  m  those  hanging  on  the  plants,  so  that  the  dropping 
of  the  squares  aids  their  good  work  as  well  as  exposes  the  squares 
to  the  heat  ot  the  sun. 


250       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Usually  about  70  per  cent  of  the  infested  squares  drop,  and  in 
these  70  to  80  per  cent  of  the  immature  stages  are  destroyed  by 
natural  causes.* 

Control. — By  far  the  most  important  measure  in  the  control  of 
the  boll  weevil  is  the  destruction  of  the  plants  in  the  fall   as 

soon  as  the  cotton  can  be  picked .  This 
both  detroys  the  weevils  and  pre- 
vents their  increase.  The  stalks 
should  be  plowed  out  and  burned  as 
soon  as  possible.  It  is  well  to  plow 
out  all  but  a  row  here  and  there 
upon  which  the  weevils  will  concen- 
trate, then  as  soon  as  the  piles  are 
dry  enough  to  burn,  cut  the  remain- 
ing rows  and ,  burn  at  once.  In  this 
way  the  great  bulk  of  the  adult 
weevils  and  all  of  the  immature  stages 
in    the    squares   and  bolls   are  des- 

^       ^,,-0  7         .  troyed.    The  few  escaping  weevils  will 

tiQ.    215. — oolenopsis    gemmata  ,         ,  ,         ,    ^     c  ji  ,^ 

Fab.,  a  native  ant  which  is  a  be  starved  out  before  the  weather 
vahiable  enemy  of  the  boll  becomes  cold  enough  for  them  to 
weevil  —  much    enlarged. 

(After  Hunter  and  Hinds,  U.  hibernate,  or  will  be  so  weakened  as 
S.  Dept.  Agr.)  ^q  ^[q  {j^   hibernation.      Thus  it  has 

been  shown  by  Professor  Wilmon  Newell,  in  Louisiana,  that 
where  the  weevils  were  forced  into  hibernation  on  October  15th 
only  3  per  cent  survived  the  winter,  but  that  when  the  destruction 
of  the  stalks  was  put  off  until  after  December  15th,  43  percent  sur- 
vived, with  proportional  numbers  at  intervening  dates.  Further- 
more, the  development  of  the  late  broods  which  furnish  the  majority 
of  the  weevils  which  hibernate  is  effectively  prevented.  The  re- 
moval of  the  plants  also  facilitates  winter  plowing,  which  aids  in  pro- 
ducing an  early  crop  the  next  year.  Many  experiments  and  the 
experience  of  practical  planters  have  shown  that  the  destruction  of 
the  stalks  in  the  fall  is  of  primary  importance  in  the  control  of  the 
weevil,  particularly  upon  bottom  lands.  Experiments  made  in 
Calhoun  County,  Texas,  where  the  stalks  were  destroyed  on  410 

*  See  W.  E.  Hinds,  Some  Factors  in  the  Natural  Control  of  the  Mexican 
Cotton  Boll  Weevil,  Bulletin  74,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  COTTON 


251 


acres,  showed  an  increase  the  next  season  of  over  one-quarter 
bale  per  acre  as  compared  with  fields  where  the  stalks  had  been 
left  standing,  the  benefit  being  worth  $14.56  per  acre,  or  over 
twenty-nine  times  the  cost  of  the  work.  It  is  better  to  plow  out 
the  stalks  than  to  cut  them,  particularly  in  the  far  South,  as  the 
stalks  will  frequently  sprout  out  in  the  late  fall  and  thus  furnish 
food  for  the  late  weevils,  or  will  sprout  in  early  spring  and  furnish 
food  for  those  first  emerging  from  hibernation.  For  the  same 
reasons  all  volunteer  cotton  should  be  destroyed. 

It  is  evident  that  the  thorough  defoliation  of  the  plants  by  the 
cotton  leafworm  will  secure  much  the  same  result  as  the  destruc- 
tion of  the  stalks,  by 
removing  the  food 
supply  of  the  weevil. 
Planters  should  not 
poison  the  leaf  worms, 
therefore,  when  they 
appear  during  the  lat- 
ter part  of  the  season 
in  fields  injured  by 
the  weevil,  for  though 
formerly  much 
dreaded  they  are  now 
a  great  aid  in  pre- 
venting the  increase 
of  the  weevil  in  fall. 

It  has  been  demon- 
strated that  injury  by 
the  weevil  is  never  so 
severe  where  cotton 
is  planted  after  some  other  crop,  this  being  due  to  the  fact  that 
the  weevils  do  not  fly  far  from  their  hibernating  quarters  in  the 
spring. 

By  hastening  the  maturity  of  the  crop,  injury  by  the  weevils 
may  be  avoided  by  making  the  crop  before  'they  have  become 
most  abundant.  Everything  possible  should  therefore  be  done 
toward  hastening  maturity,  and  this  will  be  of  importance  in  rela- 
tion to  the  early  destruction  of  the  stalks  in  the  fall.  Land  should 
be  plowed  in  the  winter  and  a  good  seed  bed  prepared.     Cotton 


Fig.  216. — Bracon  mellitor  Say,  one  of  the  most  im- 
portant parasites  of  the  boll  weevil  larvse — much 
enlarged.  (After  Hunter  and  Hinds,  U.  S.  Dept. 
Agr.) 


252        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

should  be  planted  as  early  as  possible  with  safety.  A  liberal  use 
of  commercial  fertilizers  will  hasten  the  growth  of  the  crop  even  on 
fairly  fertile  soils,  and  on  poor  soils  their  use  will  return  a  hand- 
some profit.  Early  varieties  of  cotton  should  be  planted,  among 
the  most  satisfactory  being,  Rowden,  Triumph,  Cleveland  Big 
Boll,  Cook's  Improved,  King,  Hawkins'  Early  Prolific,  and  Sim- 
kins.  Seed  should  be  secured  from  the  originators  of  the  varie- 
ties as  far  as  possible.  Chop  out  the  plants  as  soon  as  possible. 
Frequent  light  cultivation  will  be  found  of  the  greatest  importance 
in  hastening  the  crop.  Deep  cultivation  and  cultivating  close  to 
the  plants  should  be  avoided  as  causing  the  squares  to  shed,  and 
the  old  practice  of  ''  laying  by  "  by  running  a  broad  sweep  down 
the  middles  should  be  avoided.  The  lightest  possible  cultivation 
to  keep  the  surface  soil  stirred  is  the  best.  All  of  these  methods 
which  aid  in  hastening  the  maturity  of  the  crop  are  commonly 
called  "  cultural  methods  "  of  preventing  loss  from  the  weevil. 
They  are  not  directed  againts  the  weevil  itself,  but  are  merely  the 
best  agricultural  methods  for  securing  an  early  crop,  and  on  light 
upland  soils  attention  to  these  methods  will  alone  be  sufficient  to 
secure  a  good  crop. 

It  has  already  been  shown  that  the  immature  stages  in  squares 
falling  on  the  hot  soil  will  be  killed  by  the  heat.  To  aid  in  this 
the  rows  should  be  planted  fairly  wide  apart,  and  varieties  pro- 
ducing a  minimum  of  shade  are  preferable  as  are  those  which 
readily  shed  their  squares  when  injured.  As  most  of  the  squares 
drop  beneath  the  plants  where  they  are  shaded,  any  means  of 
scraping  them  into  the  centers  of  the  rows  will  aid  in  their  de- 
struction. For  this  purpose  a  chain  cultivator  as  described  by 
Hunter  (I.e.)  (Fig.  215)  has  proven  very  efficient  for  this  purpose. 
The  chains  may  be  attached  to  ordinary  cultivators  by  special 
attachments. 

During  1909  Professor  Wilmon  Newell  and  his  assistants 
demonstrated  at  several  places  in  Louisiana  that  the  weevil  may 
be  successfully  poisoned  by  the  use  of  dry  or  powdered  arsenate 
of  lead,  though  previous  experiments  with  dry  Paris  green  and 
arsenate  of  lead  as  a  liquid  spray  had  not  proven  of  practical 
value  for  various  reasons.  An  increase  of  71  per  cent  of  the  crop 
was  secured  on  considerable  areas  and  the  results  were  duplicated 
by  practical  planters.     Professor  Newell  recommends  that  the 


INSECTS  INJURIOUS  TO  COTTON 


253 


poison  be  applied  first  when  the  first  squares  appear  and  that  five 
applications  be  given  at  weekly  intervals.  The  poison  must  be 
applied  by  hand  with  a  powder-gun  so  that  it  is  blown  into  the 
squares.  The  first  application  requires  about  2^  pounds  per  acre 
and  the  last  5  to  7  pounds.  Since  that  time  there  has  been  a 
very  considerable  amount  of  experimental  work  on  boll  weevil 
poisoning  and  opinions  as  to  the  value  of  the  treatment  have  been 
variable.  All  authorities  seem  now  to  agree  that  poisoning  with 
arsenate  of  lead  or  of  calcium,  applied  in  the  form  of  a  dust,  is 
a  valuable  means  of  protection  from  the  weevil,  somewhat  more 
favorable  results  having  been  secured  from  the  arsenate  of  lead 
than  from  the  calcium  arsenate.  The  number  of  treatments  and 
the  amount  of  material  used  will  vary  somewhat  with  the  infesta- 
tion and  local  conditions  but  eight  pounds  per  acre  has  been  used 
with  profit.  Professor  Newell  puts  special-emphasis  on  applying 
the  material  so  that  it  will  cover  the  squares,  bolls  and  terminal 
buds  rather  than  the  foliage.* 


The  Pink  Bollworm  f 

An  insect  which  might  become  of  the  greatest  importance  to 
the  cotton  industry  is  the  pink  bollworm,  now  present  in  this 
country  in  only  small   areas  in  p^^^, 

Texas  and  Louisiana  and  being 
eradicated  in  that  area  by  vigor- 
ous measures  prosecuted  by  the 
Bureau  of  Entomology  of  the 
United  States  Department  of  Agri- 
culture, which  also  maintains  a 
strict  quarantine  to  prevent  the 
spread,  even  prohibiting  the  grow- 
ing of  cotton  in  certain  counties 
in  order  to  form  a  barrier  to  prog- 
ress by  creating  a  belt  where  no 
food  can  be  secured  by  the  insect.  Fig.  217. — The  pink  bollworm  {Pec- 
The  pink  bollworm  is  probably  ^"^«M«m  gossypidla) :  adult;  much 
^  ^  J       enlarged.    (After  Busck,  Jour.  Agr. 

a  native  of  southern   Asia  and      Research,  Vol.  IX,  No.  10.) 

*  See  Newell  and  Smith,  Circular  33,  La.  Crop  Pest  Comm.,  ad  Newell 
and  Bynum,  Jour.  Ec.  Ent.,  Vol.  13,  No.  1,  1920;  also  B.  R.  Coad,  U.  S. 
Dept.  Agr.,  Bulletin  731. 

t  Pectinophora  gossypiella  Saunders.  Family  Gelechiidoe.  See  W.  D.  Hun- 
ter, Bulletin  723,  U.  S.  Dept.  of  Agr. 


254      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

is  found  in  various  parts  of  Asia  and  Africa  and  in  Hawaii,  Brazil 
and  Mexico,  having  been  introduced  from  the  latter  country 
into  Texas. 

The  adult  is  a  small  moth  of  brownish  color  and  with  narrow, 

fringed  wings.     The  wing  expanse  is  never  as  great  as  one  inch. 

pin«  oonwrm  Pure  1 1        The  larva  is  a  small ,  smooth , 

}^lS^^^(^^^^^^!yf$t^1f^^  pinkish   caterpillar  with 

(^^^j^^^^^^^^^^^^^^&      eight  pairs  of  legs  and  pro- 

^'^^'^^^^^^^^^^'^^^'^^^^^^      legs,  being  in  this  respect 

very  unlike  the  boll  weevil 

'"d  JLVIfVi"'  sl;°o"rrstr°cr';    l-a  which  is  footless.     U 

much  enlarged.    (After  Busck,  Jour.  Agr.    feeds  entirely  Within    the 

Research,  Vol.  IX,  No.  10.)  ^qHs  ^nd  even  in  the  seeds 

of  cotton  and  it  is  in  the  seeds  that  it  is  most  likely  to  be  carried 

from  place  to  place. 

Since  it  is  in  the  process  of  extermination  it  is  not  necessary 
to  do  more  here  than  to  call  attention  to  the  seriousness  of  the 
insect  and  to  repeat  the  warnings  to  cotton  growers  to  report 
promptly  to  the  Federal  or  State  authorities  the  presence  of  any 
insect  which  might  possibly  be  the  pink  bollworm. 

The  Red  Spider  * 

The  so-called  red  spider  is  a  very  minute  reddish  mite  which 
attacks  a  great  variety  of  cultivated  plants  and  is  frequently 
injurious,  often  being  mistaken  for  a  fungous  disease  and  called 
a  rust.  They  pass  the  winter  mainly  as  adults  and  they  breed 
continuously  throughout  the  growing  season  of  plants,  migrating 
from  plant  to  plant  in  search  of  food.  They  are  found  over  most 
of  the  eastern  part  of  the  country  and  on  the  Pacific  coast  but 
are  much  more  abundant  in  the  cotton  growing  regions  than 
elsewhere. 

Leaves  of  badly  infested  plants  turn  yellow,  wilt,  droop  and 
finally  fall  off. 

Control  measures  recommended  as  summarized  by  McGregor 
and  McDonough,  1.  c,  are: 

"  To  prevent  injury  to  cotton  by  red  spiders  the  following 
steps  should  be  taken:  (1)  Destruction    of  all  weeds  around  the 

*  Tetranychus  telarius  Linn.  Family  Teiranychidae.  Order  Acarina. 
See  McGregor  and  McDonough,  Bulletin  416,  U.  S.  Dept.  of  Agr. 


INSECTS  INJURIOUS  TO  COTTON 


255 


farm  during  the  winter  and  early  spring;  (2)  spraying  of  culti- 
vated plants  around  the  dwellings  with  a  contact  insecticide; 
(3)  maintaining  a  finely  pulverized  surface  soil;  (4)  destruction 
of  early  infested  plants  on  large  areas  of  heavy  infestation  by 
plowing  up  and  burning;  and  finally,  if  the  infestation  is  more 


1      rf«T^' 


Fig.  219. — The  common  red  spider  {Tetranychus  telarius):  1,  the  egg;  2,  the 
newly vhatched  larva;  S,  the  recently  molted  protonymph;  4,  the  mature 
deutonymph  just  prior  to  the  final  molt;  5,  the  adult  female.  Highly 
magnified.  (After  McGregor  and  McDonough,  Bull.  416,  U.  S.  Dept. 
of  Agr.) 

or  less  general,  (5)  spraying  the  cotton  plants  with  one  of  the 
following  contact  insecticides:  Potassium  sulphide,  lime-sulfur, 
kerosene  emulsion,  or  a  flour-paste  solution." 


CHAPTER  XIV 

INSECTS  INJURIOUS  TO  POTATOES  AND  TOMATOES 

The  Potato  Stalk-borer  * 

In  some  sections  this  insect  has  rivaled  the  famous  Colorado 
potato-bug  in  the  damage  it  has  inflicted  upon  potato-vines.     It 


Fig.  220. — Work  of  potato  stalk-borer  in  potato-vines.     (After  J.  B.  Smith.) 

was   recorded   as   badly   damaging   the   crop   in   Iowa   in    1890, 

and  was  found  by  Dr.  Riley  in  Missouri  as  early  as  1869.     The 

beetles  were  first  noted  in  New  Jersey  in  1895,  and  have  been 

injurious  in  Maryland  and  most  of  the  Middle  States. 

Life  History. — The  grubs,  which  bore  into  the  stalks  of  the  vines, 

ate  the  larvae  of  some  small  ashen-gray  beetles  which  appear  early 

*  Trichobaris  trinotata  Say.     Family  Curculionidoe. 

256 


INSECTS  INJURIOUS  TO  POTATOES  AND  TOMATOES     257 


in  spring  and  into  June.  These  beetles  are  about  one-fourth  of  an 
inch  long,  with  a  long,  black  beak  or  snout,  and  are  marked  at  the 
base  of  the  wing-covers  by  three  black  spots  which  give  the  insect 
its  specific  name,  irinotata.  Each  beetle  punctures  a  small  hole  in 
the  base  of  a  stem  by  means  of  its  beak,  hollows  out  a  small  cavity, 
and  there  lays  a  single  small,  oval,  whitish  egg.  From  these  eggs 
some  small,  white  grubs  with  brown  heads  hatch  in  a  few  days  and 
commence  to  bore  into  the  stalk.  These  gru-bs  keep  eating,  either 
in  the  main  stalk  or  branches,  from  August  1st  to  September  1st, 
when  they  have  become  full  grown.  At  this  time  the  grubs  are 
about  one-half  an  inch  long,  of  a  dirty  white  or  yellowish  color, 


Fig.  221. — Potato  stalk-borer  {Trichobaris  irinotata). 
(After  J.  B.  Smith.) 


Larva,  pupa  and  adult. 


with  a  yellowish-brown,  horny  head,  and  without  legs.  About  the 
middle  of  August,  as  a  general  rule,  the  grubs  construct  small,  oval 
cocoons  of  chips  and  fibres  in  the  stalk  of  the  vine  near  the  sur- 
face of  the  soil,  and  there  transform  to  the  pupse.  During  late 
August  and  September  the  mature  beetles  shed  the  pupal  skins,  in 
which  they  have  remained  dormant  for  the  last  few  weeks,  but 
remain  in  the  vines  during  the  winter,  and  do  not  come  forth  till 
the  following  spring. 

Remedies. — On  account  of  its  internal  feeding  habits  no  poison 
can  be  successfully  used  against  this  pest,  and  the  only  remedy, 
but  a  good  one,  is  to  rake  up  the  vines  and  burn  them  as  soon  as 
the  potatoes  have  been  dug.  As  this  insect  also  feeds  upon  the 
Jamestown  weed,  horse-nettle,  and  other  weeds  of  the  Nightshade 
family,  or  Solanaceoe,  these  should  be    cut  down    very    closely. 


258       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

When  the  grubs  are  noticed  in  the  plants,  a  good  allowance  of  fer- 
tilizer will  do  much  to  quicken  growth  and  thus  enable  them  to 
mature  a  crop. 

The  Potato  Tuber-worm  * 

The  most  serious  pest  of  the  potato  in  California  is  the  Tuber- 
worm,  which  in  tobacco  regions  of  the  Southern  States  is  known 
as  the  "  split  worm  "  or  leaf -miner  (see  page  223),  Not  infre- 
quently 25  per  cent  of  the  crop  is  lost  in  infested  regions  in 
California,  injury  occurring  both  in  the  fields  and  to  the  tubers 
in  storage.  As  the  pest  is  carried  in  the  potatoes  and  breeds  in 
storage  throughout  the  warm  winters  of  California,  and  when 
exported  across  the  Pacific,  it  is  necessary  to  inspect  closely 
potatoes  from  infested  regions.  Although  no  injury  to  potatoes 
has  occurred  outside  of  California,  and  though  the  insect  probably 
could  not  exist  in  the  North,  it  may  well  be  guarded  against  in 
the  Southern  States,  where  it  is  a  common  tobacco  pest.f 

Moths  which  have  developed  from  larvae  working  in  stored 
potatoes  are  on  the  wing  when  young  potatoes  are  up,  and  lay 
their  eggs  at  the  base  of  the  leaves.  The  young  larvae  bore  into 
the  stalks,  often  causing  the  plants  to  wilt  and  die.  On  older 
plants  or  when  the  stalks  harden,  the  larvae  leave  the  stalks  and 
enter  the  tubers,  particularly  where  they  may  be  exposed.  Where 
potatoes  are  exposed  by  being  insufficiently  covered  the  moths 
will  lay  their  eggs  directly  upon  them,  as  they  also  do  upon  po- 
tatoes exposed  in  the  field  after  digging. 

Most  of  the  observations  upon  the  life  history  seem  to  have 
been  made  upon  the  insect  when  breeding  in  stored  potatoes. 
The  eggs  are  about  one-fiftieth  inch  long,  oval,  white,  and  laid 
singly  or  in  pairs,  about  the  eyes  of  the  potatoes,  or  in  similar 
rough  places,  where  they  are  seen  with  difficulty.  They  hatch 
in  a  week  or  ten  days,  and  the  young  larvae  are  about  one-twenty- 
fifth  inch  long  of  a  transparent  white  color.  The  larvae  burrow 
beneath  the  skin  and  bore  into  the  potatoes,  filling  then* 
burrows  with  grass  and  excrement,  which  soon  give  rise  to  various 
rots  which  cause  the  destruction  of  the  tuber,  already  rendered 
unfit  for  food   by  the  burrows.     The  larvae  become  full  grown 

*  Phthorimcea  opercvlella  Zell.  See  W.  T.  Clarke,  Bulletin  135,  California 
Agr.  Exp.  Sta.    Also  J.  E.  Graf  Bulletin  427,  U.  S.  Dept.  of  Agr, 

t  Recently  serious  injury  by  this  insect  has  been  reported  to  potatoes 
near  Hallettsville,  Texas. 


INSECTS  INJURIOUS  TO  POTATOES  AND  TOMATOES     259 

in  about  six  or  seven  weeks.  They  are  then  about  a  half 
inch  long.  The  head  is  dark  brown;  the  first  segment  is  an 
old  rose  color,  with  dark  brown  shield  on  the  back;  the  second 
segment  is  a  similar  clouded  pink;  while  the  third  and  succeeding 
segments  are  a  clouded  white,  often  becoming  yellowish  or  green- 
ish, according  to  the  food  eaten.  The  full-grown  larva  re- 
turns to  the  mouth  of  the  burrow  and  there  makes  its 
cocoon,  or  leaves  it  and  forms  the  cocoon  in  some  depression  of 
the  potato  or  in  some  crack  of  the  storage  vessel  or  in  a  fold 
of  the  bag.  The  cocoon  is  constructed  quite  differently  from 
that  of  most  moths,  as  described  by  Mr.  Clarke.  The  larva  first 
makes  a  mat  of  silk  and  then  forms  an  outer  layer  to  the  surface 
of  which  particles  of  dirt  and  rubbish  adhere  so  that  the  cocoon 
is  well  concealed.  When  this  pocket-like  cocoon  is  finished  the 
larva  enters  it  and  closes  the  open  end  and  in  it  transforms  to 
the  pupa.  The  pupal  stage  lasts  about  two  weeks,  so  that  the 
complete  life  cycle  requires  from  nine  to  twelve  weeks,  there  being 
several  generations  during  the  year,  according  to  the  temperature. 
Control. — As  the  insect  breeds  on  various  common  weeds  of 
the  Nightshade  family  {Solanacece) ,  it  is  important  that  they  be 
destroyed  wherever  found.  Seed  potatoes  must  be  free  from  the 
larvae,  or  they  will  soon  give  rise  to  moths  which  will  infest  a 
whole  field.  When  young  plants  are  found  wilting,  the  infested 
stalks  should  be  cut  and  destroyed  as  soon  as  possible  to  prevent 
the  further  development  and  spread  of  the  pest.  Care  should 
be  taken  in  cultivating  to  hill  up  the  soil,  or  thoroughly  cover 
the  tubers,  so  that  they  are  not  exposed.  After  digging,  the 
potatoes  should  not  be  left  exposed  in  the  field  any  longer  than 
is  absolutely  necessary  and  should  not  be  covered  with  the  tops 
to  shade  them,  as  is  often  done,  as  this  furnishes  a  shelter  for  the 
moths  and  induces  oviposition  upon  the  tubers.  Infested  fields 
should  have  the  stalks  and  all  rubbish  and  refuse  thoroughly 
raked  up  and  burned  as  soon  as  possible,  or  sheep  and  hogs  may 
be  turned  into  the  fields  to  destroy  the  stages  which  may  be 
left  in  the  vines  or  in  the  soil.  Where  fields  have  been  flooded 
for  two  or  three  weeks  after  the  crop  has  been  dug,  they  have 
been  entirely  freed  of  the  pest.  For  the  treatment  of  stored 
potatoes,  fumigation  with  carbon  bisulfide  in  a  tight  room 
seems  to  be  the  only  satisfactory  method.     This  should  be  done 


260       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


as  described  for  grain  insects  (see  page  187).  The  tubers  should 
be  fumigated  as  soon  as  stored,  and  the  treatment  should  be 
repeated  at  intervals  of  two  weeks,  foiu-  or  five  fumigations 
being  recommended  to  free  the  potatoes  entirely  of  all  stages. 
Obviously  it  will  be  important  to  sort  over  infested  tubers  and 
remove  all  which  are  materially  injured  to  prevent  the  increase 
of  rot  in  others. 

Colorado  Potato-beetle  * 

First  and  foremost  among  the  enemies  of  the  potato-grower 
stands  the  Colorado  potato-beetle — the  insect  which  in  the  early 
seventies,  on  account  of  our  ignorance  of  it,  was  made  an  entomo- 


PlG.  222. — The  Colorado  potato-beetle  {Leptinotarsa  decemlineata  Say.):  a, 
eggs;  b,  larva;  c,  pupa;  d,  beetle;  e,  elytra  or  wing-cover  of  beetle; 
/,  leg  of  beetle.     (After  Riley.) 

logical  bugbear.  But  "there's  no  great  loss  without  some  small 
gain,"  and  we  may  be  thankful  that  the  invasion  of  this  beetle 
also  brought  about  the  use  of  Paris  green,  an  insecticide  which  has 
since  saved  millions  upon  millions  of  dollars  to  the  American 
farmer.  Thus,  with  an  effectual  remedy  which  is  nov/  used  where 
this  pest  occurs  as  regularly  as  potatoes  are  planted, "  familiarity 
has  bred  contempt/'  and  to-day  we  have  but  little  fear  of  its 
attack. 

*  Leptinotarsa  decemlineata  Say.     Family  ChrysomelidrB.     See  F.  H.  Chit- 
tenden, Circular  87,  Bureau  of  Entomology,  U.  S.  Agr.  Dept. 


INSECTS  INJURIOUS  TO  POTATOES  AND  TOMATOES     261 

History. — As  is  probably  known  to  most  of  the  older  genera- 
tion who  watched  its  spread  eastward,  the  Colorado  potato-beetle, 
as  its  name  indicates,  was  a  native  of  the  Rocky  Mountain  region, 
and  until  about  1855  was  satisfied  with  feeding  upon  various  com- 
mon weeds  of  the  same  genus  as  the  potato-plant,  principally 
Solanum  datura,  and  closely  allied  genera.  But  with  the  settle- 
ment of  this  country  and  the  introduction  of  the  Irish  potato, 
these  bugs  also  began  to  take  advantage  of  the  fruits  of  civilization 
and  transferred  their  feeding-grounds  from  the  roadside  to  the 
potato-patch,  and  rapidly  spread  eastward  from  one  to  another, 
as  well  as  being  transported  in  the  shipping  of  the  potatoes. 

Thus,  in  1859  they  had  reached  a  point  one  hundred  miles  west 
of  Omaha,  Neb. ;  five  years  later  they  crossed  the  Mississippi  into. 
Illinois;  and  they  advanced  steadily  eastward  till  recorded  in 
the  Atlantic  States  in  1874.  Though  slow  to  be  introduced  into 
some  few  sections  of  the  country,  it  is  safe  to  assert  that  this  pest 
may  to-day  be  found  almost  wherever  the  potato  is  grown  in  the 
United  States  or  southern  Canada. 

Life  History. — During  October  the  beetles  enter  the  earth  and 
there  hibernate  till  the  warm  sunshine  of  April  or  May  brings 
them  forth.  As  soon  as  the  young  plants  appear,  the  female 
beetles  deposit  their  yellow  eggs  upon  the  underside  of  the  leaves 
near  the  tips,  each  female  laying  an  average  of  about  five  hundred 
eggs  during  the  course  of  a  month.  Meanwhile  the  beetles  have 
done  considerable  damage  by  eating  the  young  and  tender  plants. 
In  about  a  week  there  hatch  a  horde  of  very 
small  but  very  hungry  larvse,  which  fairly 
gorge  themselves  with  potato-foliage  and 
increase  in  size  with  astonishing  rapidity. 
In  two  and  a  half  to  three  weeks,  after 
having  eaten  an  amount  of  food  out  of    «         j     '  J^ 

all  proportion  to  their  size,  the  larvae  become  Fiq.  223. a,  beakof  pre- 

full  grown,  and  enter  the  earth,  where  they      daceous  bug;  b,  Podi- 
„  J,  1       11  1   ,  c  s^s  spinosus   Dall.;  c, 

lorm  smooth,  oval  cells,  and  transform  to      beak  of  plant-feeding 

pupa?.     In  a  week  or  two  the  adult  beetles      bug.    (After  Riley.) 
emerge  from   the  pupal  skins  and  after  feeding  for  a  couple  of 
weeks,  deposit  eggs  for  a  second  generation,  which  develops  in 
the  same  way,  and  the  beetles  from  which  hibernate  as  already 
described.      Throughout  the  territory  where  the  beetles  are  most  in- 


262        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

jurious  there  are  two  generations  a  year,  but  further  south  there 
is  evidence  of  at  least  a  partial,  if  not  complete,  third  generation, 
and  in  the  northern  range  of  the  species  there  is  but  one  gen- 
eration a  year. 

Natural  Enemies. — One  of  the  chief  agencies  to  prevent  the 
excessive  multiplication  of  this  pest  is  the  weather.  Thus,  Pro- 
fessor Otto  Lugger  records  that  in  Minnesota,  late  in  the  fall 
of  1894,  the  beetles  were  lured  from  their  winter  quarters  by  a 
few  warm  days,  and  most  of  them  subsequently  perished  from 
hunger  or  frost.  In  addition  to  this  during  the  late  summer  of 
1894  there  was  an  excessive  drouth,  so  that  but  few  of  the  second 
brood  matured.  Thus  in  1895  there  were  very  few  of  the  in- 
sects to  be  seen. 

Among  the  birds,  the  common  crow,  the  red-breasted  gros- 
beak, and  turkeys  often  feed  upon  this  pest  to  a  considerable 
extent. 

Probably  the  most  destructive  insect-parasite  of  the  larvse  is  a 
Tachinid-fly  known  to  science  as  Lydella  doryphorce  Riley,  which 

rather  closely  resembles  the  com- 
mon house  fly,  both  in  size  and 
color.  A  single  egg  is  laid  on  a 
potato  bug  and  from  it  hatches  a 
small,  footless  maggot  which  bur- 
rows inside  the  bug.  When  the 
larva  enters  the  earth,  the  effect 
of  the  maggot's  work  becomes  ap- 
parent, and  instead  of  transform- 

^  ,  ing  to  a  pupa  and  beetle,  it  shrivels 

Fig.  224. — Tachinid  parasite  of  Col-  ^     ^   ^^                    .  -^     m 

orado potato-beetle  (Lydella dory-  up  and  dies;  but  the  maggot  itselt 

phorce  Ril.).    (After  Riley.)  contracts  into  a  hard,  brown  pupa, 

from  which  the  fly  eventually  emerges.  Thus  in  1868,  when 
first  noted  by  Dr.  C.  V.  Riley,  he  asserted  that  in  Missouri  fully 
10  per  cent  of  the  second  brood  and  one-half  of  the  third  were 
destroyed  by  this  parasite. 

Many  of  our  common  lady-bird  beetles  and  their  larvse  check 
the  pest  by  feeding  upon  the  eggs.  Several  predaceous  bugs,  par- 
ticularly the  spined  soldier-bug  (Podisus  spinosus  Dall.)  (Fig.  223) 
are  of  value  in  destroying  the  larvae,  into  which  they  thrust  their 
short,  powerful  beaks,  and  then  suck  out  the  juices  of  the  body, 


Fig.  225.  —  Fieldsprayer,  with  modifications,  adapted  for  potato  spray- 
ing by  L.  C.  Corbett,  operating  at  the  Virginia  Truck  Experiment  Station, 
Norfolk,  Va.  263 


264        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


leaving  an  empty  skin.  One  or  two  of  these  closely  resemble  the 
common  squash-bug  (Anasa,  tristis  De  G.),  but  are  really  very 
dissimilar,  and  whereas  the  beaks  of  the  predaceous  forms  are 
short  and  thick  as  in  Fig.  223,  a,  those,  of  plant-feeders,  like  the 
squash-bug,  are  long  and  slender,  as  in  Fig.  223,  6. 

Several  species  of  ground-beetles  are  often  found  preying  upon 
the  larvae  and  beetles,  but,  unlike  the  bugs,  attack  them  by  means 


Fig.  226. — Murky  ground-beetle  (Harpalus  caliginosus) :  a,  its  larva;   h,  head 
of  larva  showing  mouthparts.     (After  Riley.) 

of  their  powerful  biting  jaws.     These  beetles  are  also  exceedingly 

beneficial  in  feeding  upon  many  other  injurious   insects,  and  are 

among  the  farmers'  best  insect  friends  (Fig.  227) . 

Remedies.  — As  an  artificial  remedy  for  this  pest,  Paris  green 

has  long  been  proven  to  be  both  effectual  and  practical.     For 

small  areas  it  may  be  used  dry 
by  mixing  it  with  fifty  times 
its  weight  of  dry  flour,  land- 
plaster,  or  air-slaked  lime, 
and  should  be  applied  while 
the  plants  are  still  wet  with 
dew,  either  by  a  perforated 
can,  or,  better,  by  one  of  the 

^  ,  improved    powder-guns   by 

Fig.  227.  —  Power   sprayer  adapted  for  r      i  •  i    ^  e 

spraying  several  rows  of  plants  at  one  means  01  which  two  rows  of 

time.  Courtesy  the  Bean  Spray  Pump  Co.  plants  may  be  powdered  at 

once.  On  larger  areas  spraying  will  be  found  more  satisfactory. 
One  pound  of  Paris  green  and  1  pound  of  freshly  slaked  quick- 
lime to  50  gallons  of  water  will  kill  all  the  larvae,  but  often  2  to  3 
pounds  are  necessary  to  destroy  the  beetles. 


POTATO 
BEETLE 


with 

ARSENATE  OF  LEAD 

OR  OTHER  ARSENICAL 


Use  arfenateof  lead  in  proportion  of  2  pounds  of 
powdered  form(or  4  Its  of  pastejto  50  fallens  of 
water.  Mix  first  with  small  quantity  of  water  and 
then  stir  thoroughly  into  the  full  amount. 

If  arseuite  of  zinc  or  arsenate  of  lime  is  used 
follow-  directions  on  package 

Apply  with  a  good  pump  throwing  a  fine^. 
mist.  Cover  the  foliaje  completely:  , 

Be?in  sprayinjv/henthe  beetles  first  appearli 
Spray  for  the  5lu?s  when  the  eg?s  are  hatching^ 
and  repeat  as  often  as  necessary. 
T 


/'     Infall  beetles  reenter  rrcorJ  to  spend  winter.  Insprin;  tKey  '^ 
'  emei^e  to  feed  on  the  younj  plants, TheatHc  females  .'s/ thejresjs  / 
^  onunifr  sides  of  kav^es. which  product  first  ?srerat;cnof  sluss.  (((j' 


Fig.  228. — Bureau  of  Entomology,  U.  S.  Department  of  Agriculture,  popular 
poster  on  the  potato-beetle, 

265 


266      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Many  growers  now  prefer  to  use  arsenate  of  lead  at  from  3  to  5 
pounds  to  the  barrel,  as  there  is  no  danger  of  burning  the  foliage 
with  it,  and  it  is  much  more  adhesive.  Where  Bordeaux  mixture 
is  not  used  the  arsenate  of  lead  is  much  preferable  on  account  of  its 
superior  adhesiveness.  Where  Bordeaux  mixture  is  used,  arsenite 
of  lime,  or  arsenite  of  lime  made  with  soda,  may  be  used,  but  these 
homemade  arsenicals  should  not  be  used  alone,  on  account  of 
their  burning  the  foliage. 

The  vines  should  be  sprayed  first  when  they  are  a  few  inches 
high,  and  the  spraying  repeated  once  or  twice  at  intervals  of  ten 
days  or  two  weeks.  The  larvae  are  so  easily  killed  by  arsenicals 
that  potato  growers  no  longer  fear  their  work,  but  large  quantities 


Fig.  229. — The  convergent  ladybird  {Hippodamia  convergens) :    a,  adult;    6 
pupa;  c,  larva;  enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

of  Paris  green  are  wasted  by  careless  application,  and  by  dusting 
unduly  large  amounts  with  poor  apparatus,  which  not  infrequently 
results  in  burning  the  foliage.  For  small  areas  a  bucket  or  knap- 
sack pump  will  be  found  satisfactory,  but  for  over  an  acre  a  barrel 
pump  with  a  row  attachment  will  prove  more  economical,  and  for 
over  ten  acres  a  geared  machine  spraying  several  rows  at  once  will 
be  needed.  Cleaning  up  the  vines  and  plowing  potato  land  in  the 
fall  after  the  crop  has  been  harvested  will  aid  in  reducing  the  num- 
bers of  the  hibernating  beetles. 

Flea-beetles  * 

While  the  potatoes  and  tomatoes  are  but  a  few  inches  high  they 
are  often  attacked  by  myriads  of  small  black  beetles,  which  from 

*  Family  Chrysomelidoe. 


INSECTS  INJURIOUS  TO  POTATOES  AND  TOMATOES     267 

their  power  of  making  long  quick  jumps  are  known  as  flea-beetles. 
They  soon  riddle  the  foliage,  often  so  badly  that  the  plants  wilt,  and 
replanting  is  necessary,  particularly  with  tomatoes. 

Several  species  are  known  to  attack  the  potato,  the  two  most 
common  being  the  potato  or  cucumber  flea-beetle  {Epitrix  cucum- 
eris  Harris)  and  one  which  Professor  H.  A.  Garman  has  styled  the 
Southern  Potato  Flea-beetle  (Epitrix  fuscula).  The  Tobacco  Flea- 
beetle  (Epitrix  parvula)  is  not  uncommonly  found  on  the  vines  in 
sections  where  tobacco  is  also  grown,  and  other  species  do  similar 
injury  in  other  sections.  All  of  these  species  are,  however,  essen- 
tially the  same  in  habits  and  life  history,  and  the  same  remedies 
apply  to  all. 

The  potato  flea-beetle*  is  the  most  destructive.  It  is  only 
one-sixteenth  inch  long,  jet  black,  except  the  yellowish  antennae 


a  b 

Fig.  230. — o,  potato  flea-beetle;    b,  egg-plant  flea-beetle,  both  greatly  en- 
larged.    (After  Chittenden,  U.  S.  Dept.  Agr.) 

and  legs,  and  there  is  a  deep  groove  across  the  base  of  the  thorax 
(Fig.  230,  a).  It  seems  to  occur  throughout  the  United  States, 
but  is  more  commonly  injurious  in  the  North.  Eggplant  and 
tobacco,  as  well  as  numerous  garden  vegetables  are  similarly 
injured.  This  species  has  commonly  been  called  the  cucumber  flea- 
beetle  from  its  specific  name,  but  it  is  evidently  a  misnomer,  as  it 
is  much  more  abundant  upon  the  potato  and  related  plants. 

During  the  winter  the  beetles  hibernate  under  leaves,  rubbish, 
etc.,  and  in  the  spring  come  forth  and  lay  their  eggs  upon  the 
roots  of  some  of  our  common  weeds  of  the  Nightshade  family, 
such    as    the   horse-nettle,    Jamestown- weed,    Desmodium,    etc., 

*  Epitrix  cucumeris  Harris.  See  O.  A.  Johannsen,  Bulletin  211,  Maine 
Agr.  Expt.  Sta. 


268       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

in  May  and  June.  The  larvae  mine  in  the  roots  of  these  plants 
and  transform  to  pupae  in  small  earthen  cells  among  the  roots, 
from  which  the  beetles  come  forth  in  the  spring  to  attack  the 
foliage  of  the  plants  mentioned.  According  to  Johannsen,  (1.  c.) 
the  larvae  feed  mainly  on  the  roots,  root-stalks  and  tubers  of  the 
potato.  When  they  feed  on  the  tubers  they  are  responsible 
for  the  condition  described  by  growers  as  "  pimply  potatoes." 
There  is  but  one  generation  per  year  in  Maine  and  probably  in 
the  Northern  States  generally,  according  to  the  same  authority. 

Injury  is  usually  due  to  the  feeding  of  the  adult  beetles  which 
have  come  out  of  hibernation  in  the  spring.  These  riddle  the 
leaves  by  their  feeding,  with  small  holes  which  look  like  they 
might  have  been  made  by  a  charge  of  fine  birdshot.  Occasionally 
the  larvae  injure  seed  tubers  in  the  spring,  but  this  is  rare. 


Fig.  231. — Larva  of  potato  flea-beetle.     (After  Johannsen,  1.  c.) 

The  Eggplant  Flea-beetle*  so  nearly  resembles  the  previous 
species  that  it  will  not  be  distinguished  from  it  but  by  the  entomol- 
ogist. It  is  slightly  larger,  however,  with  the  wing-covers  more 
hairy,  and  the  groove  at  the  base  of  the  thorax  is  not  so  distinct. 
It  has  much  the  same  food-plants,  but  is  particularly  abundant 
on  eggplant,  and  is  more  commonly  injurious  in  the  South,  below 
the  Ohio  and  Potomac  rivers. 

The  Tobacco  Flea-beetle  f  has  been  previously  discussed 
(page  212)  but  should  be  mentioned,  as  it  is  commonly  injurious 
to  potato,  tomato,  and  eggplant  throughout  the  South,  as  well 
as  to  tobacco,  and  occasionally  to  corn  and  other  plants. 

Control. — It  has  been  found  that  Bordeaux  mixture  acts  as 

an  excellent  repellant  against  these  little  beetles,  and  that  plants 

well   covered   with   it   are   not   seriously   injured.     Inasmuch  as 

it  is  always  advisable  to  spray  potatoes  as  soon  as  they  are  a 

few  inches  high  for  fungous  diseases  and  for  the  Colorado  potato 

beetle,  by  applying  the  spray  as  soon  as  possible  after  the  plants 

*  Epitrix  fuscula  Cr. 
t  Epitrix  parvula  Fab. 


INSECTS  INJURIOUS  TO  POTATOES  AND  TOMATOES    269 

are  up  they  will  be  protected.  Both  potatoes  and  tomatoes 
should  be  sprayed  with  Bordeaux  mixture  and  arsenate  of  lead 
or  Paris  green  as  soon  as  they  are  a  few  inches  high.  The  spray 
should  be  applied  liberally  so  as  to  give  the  plants  a  distinct 
coating  of  the  mixture.  Tomatoes  are  particularly  susceptible 
to  injury  and  might  be  dipped  in  arsenate  of  lead  when  planting, 
using  1  pound  to  10  gallons  of  water.  The  destruction  of  the 
weeds  upon  which  the  larvae  commonly  develop  is  obviously 
important  in  preventing  their  multiplication. 

Where  injury  by  the  larvae  is  done  to  the  tubers,  it  is  recom- 
mended that  they  be  dug  as  soon  as  possible,  and  be  left  ex- 
posed to  the  sun  for  a  few  hours  after  digging  so  as  to  harden  the 
skin,  before  being  stored.  If  damage  continues  in  storage,  the 
tubers  may  be  fumigated  with  carbon  bisulfide,  as  recommended 
for  grain  insects. 

Potato-scab  and  Insects 

That  certain  forms  of  what  is  commonly  termed  "potato- 
scab"  are  due  to  the  work  of  insects  has  frequently  been  shown. 
In  1895  Professor  A.  D.  Hopkins,*  of  the  West  Virginia  Agricultural 
Experiment  Station,  reported  some  very  careful  original  investiga- 
tions upon  two  species  of  gnats,  Epidapus  scabies  Hopk.  and  Sciara 
sp.,  the  larvse  of  which  had  been  conclusively  shown  to  cause 
a  "scab''  upon  the  tubers  by  boring  into  them.  The  larvae 
or  maggots  of  the  Potato-scab  Gnat  are  about  one-sixth  of  an 
inch  long,  and  are  the  young  of  a  wingless  gnat  shown,  very 
greatly  enlarged,  in  Fig.  232.  The  females  deposit  their  eggs  on 
the  potatoes  in  storage  from  autumn  to  spring,  and  the  maggots 
hatching  from  them  enter  old  scab  spots  or  injured  places.  Under 
favorable  conditions  a  generation  may  be  developed  in  twenty 
to  twenty-five  days.  Later  in  the  spring  the  eggs  are  deposited 
in  manure  or  other  decomposing  material,  on  seed  potatoes  or 
on  growing  tubers  to  which  they  may  be  carried  on  seed  potatoes. 
When  they  become  well  established  in  a  potato,  it  is  soon  de- 
stroyed if  they  are  not  overcome  by  their  natural  enemies,  or 
unless  the  soil  becomes  dry,  when  they  soon  disappear.  In- 
fested places  look  very  much  like  the  ordinary  scab  produced 
by  the  scab  fungus  and  ma.y  be  readily  mistaken  for  it.     Such 

*  A.  D.  Hopkins,  Special  Bulletin  2  (Vol.  IV,  No.  3),  W.  Va.  Agr.  Exp. 
Sta.,  p.  97. 


270        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


injury  was  quite  general  and  serious  in  West  Virginia  in  1891  and 
1892.  Dr.  Hopkins  found  that  "they  breed  in  and  are  especially 
common  in  barnyard-manure,"  that  "excessive  moisture  in  the 
soil  has  been  observed  to  be  the  most  favorable  condition  for 
their  development,"  and  that  "soaking  the  seed-potatoes  in  a 
solution  of  corrosive  sublimate  previous  to  planting  "  will  kill  all 
the  eggs  and  young  larvae,  as  it  will  also  destroy  the  spores  of 
the  potato-scab  fungus. 

Professor  H.  Garman*  has  also  recorded  the  injuries  of  several 
species  of  millipedes,  or  "thousand-legged  worms,"  Cambala 
annulata  and  Parajulus  impressus,  as  causing  a  scab  by  gnawing 
into  the  surface  of  the  tubers.  Though  both  of  these  observations 
are  unquestionably  true,  such  injury  has  not  occurred  in   other 


Fig.  232. — Potato  scab-gnat  {Epidapus  scabei  Hopk.);    a,  fly;    i,  larva;    g, 
egg;  h,  egg  mass — much  enlarged.     (After  Hopkins.) 

parts  of  the  country,  and  it  is  improbable  that  any  large  portion 
of  potato-scab  is  due  to  these  insects.  Potato-scab  is  a  fungous 
disease,  which,  as  already  noted,  may  be  destroyed  by  soaking 
the  seed-potatoes  in  a  solution  of  corrosive  sublimate. 

Blister-beetles  f 

Long  before  we  had  made  the  acquaintance  of  the  Colorado 
potato-beetle,  several  species  of  blister-beetles  frequently  brought 
themselves  into  notice  by  their  injuries,  and,  therefore,  are  now 
known  as  the  "old-fashioned  potato-bugs."  The  name  of 
"blister-beetles"  has  been  bestowed  upon  them  because  of  the 
blistering  effect  which  they  have  upon  the  skin,  they  being  nearly 
related  to  the  Spanish  fly,  used  for  that  purpose. 

One  of  the  most  common  of  these  is  the  Striped  Blister-beetle, 
which    has    three    yellow    stripes    upon    its    wing-covers,    while 

*  H.  Garman,  Bulletin  61,  Ky.  Agr.  Exp.  Sta.,  p.  18. 
t  Family  Meloidae. 


INSECTS  INJURIOUS  TO  POTATOES  AND  TOMATOES    271 

two  other  common  forms  are  of  a  slate-black  color.  Very  often 
when  these  beetles  congregate  in  numbers  they  are  a  great 
nuisance,  not  only  in  the  potato-patch,  but  upon  many  other 
plants  of  the  garden  or  truck-farm. 

Unfortunately,  they  present  to  the  farmer  a  very  peculiar 
problem,  for  while  the  beetles  are  often  exceedingly  injurious, 
the  larvae  are  beneficial,  eating  large  quantities  of  grasshoppers' 
eggs 

Life  History. — The  life  of  these  insects  is  unique.  The  female 
lays  a  large  number  of  eggs  in  a  small  cavity  in  the  earth,  and 
from  these  hatch  some  small,  long-legged  larvae,  which  run  about 
searching  for  the  pod-like  masses  of  grasshoppers'  eggs,  upon 
which  they  feed.  As  soon  as  the  appetite  of  one  of  these  little 
egg-hunters  is  appeased,  he  sheds  his  skin,  and  now  being  sur- 
rounded by  food  and  no  longer  needing  his  long  legs  for  running, 
in  the  next  stage  of  his  existence  his  legs  become  very  short  and 
rudimentary,  and  he  remains  almost  immobile  while  feeding  upon 
the  rest  of  the  eggs 

Control. — Spraying  with  Paris  green  or  arsenate  of  lead,  as 
advised  for  the  Colorado  potato-beetle  will  kill  the  beetles,  and 
where  the  vines  have  been  regularly  sprayed  but  little  trouble 
will  be  had  with  them  Where  they  suddenly  appear  in  large 
swarms  in  gardens  or  on  truck  land,  they  are  often  destroyed  by 
a  line  of  men  and  children  slowly  driving  them  with  branches,  as 
the  beetles  move  but  slowly  If  a  ditch  is  available  it  may  be 
oiled,  and  the  beetles  destroyed  like  grasshoppers,  or  they  may 
be  driven  into  a  windrow  of  straw,  hay,  or  any  inflammable  rubbish 
and  burned  in  it. 

Three-lined  Leaf-beetle  * 

Closely  related  to  the  Colorado  potato-beetle,  and  very 
similar  to  it  in  habits,  is  the  Three-lined  Leaf-beetle.  The  eggs 
may  be  distinguished  by  the  fact  that  they  are  usually  laid  in 
rows  along  the  midrib  on  the  under  side  of  the  leaf,  while  those 
of  the  potato-beetle  are  laid  indiscriminately  in  bunches.  The 
larvae,  however,  may  be  readily  distinguished  from  all  other 
insects  attacking  the  potato  by  being  covered  with  a  disgusting 
mass  of  their  own  excrement. 

*  Letna  trilineata  Oliv.     Family  Chrysomelidoe. 


272       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Fig.  233.  — Three-lined  leaf-beetle  {Lema  trilineata 
Oliv.);  «,  larva;  b,  pupa;  d,  eggs;  beetle  at  right. 
(After  Riley.) 


There  are  two  broods  during  the  season,  the  larvae  of  the  first 
appearing  in  June,  and  those  of  the  second  in  August;  but  the 
beetles  of  the  second  brood  do  not  emerge  until  the  following 
spring.  In  other  respects  the  life  history  is  practically  the  same 
as  that  of  the  Colorado  potato-beetle.     The  beetle  is  of  a  pale 

yellow    color,    with 
three  black  stripes  on 
its  back,  and  in  a  gen- 
eral way  resembles 
the  common  striped 
cucumber  -beetle 
(Diabrotica  vittata 
Fab.),    though   it   is 
somewhat  larger  and 
the  thorax  is  decid- 
edly constricted. 
In  case  it  becomes  necessary  to  destroy  the  blister-beetles,  both 
they  and  the  three-lined  leaf-beetle  may  be  readily  disposed  of  by 
applying  arsenicals  as  advised  for  the  Colorado  potato-beetle. 

The  Potato  Aphids  * 

The  potato  aphid,  also  called  the  pink  and  green  aphid  of 
the  potato  because  it  occurs  in  both  these  colors,  is  a  widely 
distributed  pest  which  occasionally  does  a  considerable  amount 
of  injury  to  the  potato.  It  attacks,  beside  the  potato,  the  pepper 
vine  and  several  other  unrelated  plants. 

The  insect  is  large  for  an  aphid,  and  may  be  either  pink  or 
green,  and  lacks  the  dark  markings  characteristic  of  many  species 
of  aphids. 

The  aphids  are  found  in  the  spring  and  early  summer  feeding 
on  rose  bushes  and  possibly  other  plants  and  from  these  they 
migrate  about  mid-summer  to  potato  and  other  food  plants. 
Both  winged  and  wingless  forms  migrate,  an  unusual  occurrence 
as  ordinarily  only  winged  individuals  take  part  in  the  migration. 
In  late  summer  and  early  fall  the  reverse  migration  takes  place. 

Not  a  great  part  of  the  season  is  spent  on  the  potato  but  in 
the  time  the  aphids  are  present  they  are  able  to  do  a  great  amount 


*  Macrosiphum  solanifolii  Ashmead. 
242,  Maine  Agr.  Expt.  Sta. 


See  Dr.  Edith  M.  Patch,  Bulletin 


INSECTS  INJURIOUS  TO  POTATOES  AND  TOMATOES     273 

of  damage  when  they  are  at  all  numerous.  In  addition  to  the 
direct  injury  the  aphids  do  they  create  conditions  favorable  for 
fungus  attack,  the  wounds  made  by  their  beaks  serving  as  points 
of  infection  and  the  weakened  condition  of  the  plants  making 
them  less  resistant. 

This  species  has  been  reported  from  Maine  and  California 
and  in  many  intermediate  localities. 

Control. — Dr.  Patch,  (1.  c  ),  states  that  since  the  insect  winters 


Fig.  234. — The  potato  aphid.     Winged  summer  form. 

Agr.  Expt.  Sta.) 


(After  Webster,  Iowa 


in  the  egg  stage  on  many  plants  near  potato  fields,  clean  culture 
and  destruction  of  weeds  in  the  fall  should  be  a  valuable  means 
of  control.  She  recommends,  also,  spraying  rose  bushes  showing 
infestation  in  the  spring  with  tobacco  extract  and  later,  if  necessary 
spraying  the  potatoes  with  the  same  material. 


The  Apple  Leafhopper  * 

The  apple  leafhopper  is  so  named  from  the  fact  that  it  is  found 
on  apples,  especially  on  young  trees  in  the  nursery.  To  these 
it  is  quite  seriously  injurious,  being  often  the  most  important 
insect  pest  found  in  apple  nurseries.  It  is  called  also  the  potato 
leafhopper  because  it  attacks  potatoes  and  is  even  more  injurious 

to  them  than  it  is  to  the  apple. 

/^ 

I  *  Etnpoasca  niali  LeBaron.  P'amily  Jassidce.  See  Bulletins  111  and  155, 
Iowa  Expt.  Sta.,  E.  D.  Ball,  Journal  of  Econ.  Ent.,  Vol.  12,  No.  2,  1919, 
pp.  149-154. 


Fig.  235.— The  apple  leafhopper.  (After  A.  J.  Ackerman,  Bull.  805,  U.  S.  Dept. 
of  Agr.)  A,  first  nymphal  stage;  B,  second  stage;  C,  third  stage;  D,  fourth  stage; 
E,  fifth  stage;  F,  side  view  of  fifth  stage;  G,  adult;  H,  front  view  of  head  of 
adult;  /,  eggs  in  tissue  on  underside  of  apple  leaf;  J,  curled  condition  of  ter- 
minal leaves  due  to  attack  by  the  apple  leafhopper  on  apple. 

274 


INSECTS  INJURIOUS  TO  POTATOES  AND  TOMATOES     275 

The  leaf  hopper  in  question  is  a  small  insect  of  slender  form, 
about  one-eighth  inch  in  length.  The  adults  have  wings  and  are 
also  provided  with  hind  legs  fitted  for  hopping  and  are  quite 
active.  The  young  hop  to  some  extent  but  are  much  less  active 
than  the  adults. 

They  winter  usually  as  adults  but  are  said  also  to  pass  the 
winter  in  the  egg  stage,  the  eggs  being  laid  in  the  fall  on  the  food 
plant.     There  are  tliree  or  four  generations. 

Injury  to  potato  is  of  two  kinds;  first,  the  direct  injury  due 
to  the  sucking  of  sap  by  the  leafhopper  and  second,  the  blighting 
of  the  leaves  said  to  be  caused  by  the  leafhopper.  There  is  some 
doubt  as  yet  as  to  just  how  much  the  leafhoppers  have  to  do 
with  the  transmission  of  the  disease  which  is  called  the  tip-burn  or 
hopper-burn  but  Dr.  Ball,  (1.  c.)  has  presented  a  very  strong  case 
against  the  hopper.  He  maintains  that  the  tipburn  is  the  result 
of  a  specific  poison  injected  by  the  hoppers  or  a  specific  infection 
carried  by  them.  The  evidence  may  not  be  quite  conclusive 
and  is  still  the  subject  of  investigation,  but  there  are  at  least  strong 
probabilities  that  the  case  against  the  hoppers  will  be  proven. 
The  problem  is  complicated  by  the  fact  that  there  may  be  more 
than  one  kind  of  tipburn  or  tip  blight,  as  a  trouble  of  very  similar 
nature  has  been  observed  by  the  writer  in  fields  where  no  leaf- 
hoppers  were  to  be  found.  This  burn  was  generally  ascribed 
to  weather  conditions. 

Control. — Control  measures  against  this  pest  on  potato  have 
not  been  very  well  worked  out,  but  it  is  probable  that  clean  culture 
and  spraying  with  nicotine  preparations  will  be  found  to  give 
the  best  results. 

Tomato  Worms 

The  large  green  horn-worms  which  attack  the  foliage  of  the 
tomato  are  the  same  as  those  previously  described  which  attack 
tobacco.  Usually  they  ate  not  so  numerous  but  that  they  may 
be  readily  controlled  by  handpicking,  but  if  necessary  the  same 
remedial  measures  may  be  used  as  advised  for  them  on  tobacco. 

The  Tomato  Fruitworm 

The  worms  which  commonly  bore  into  the  green  and  ripening 
tora,atoes  are  the  same  as  the  tobacco  budworm  and  the  cotton 


CARDEN 

CUTWORMS 


Young"  cucumber 

plant  cut  off  at  root 

by  cutworm  and  end 

drag"ged  into  burrow 

to  be  eaten. 

Young"  catbag-e  plant 

destroyed  by  a  cutNArorm. 

The  culprit  hiding'  in  ground  /  ■       , ., 
durincf  day  near  «"^W,.>ly 

the  plant. 


summer 

The  moths  lay 
e§5's  on  grasses  or 
'^/Z^iry ''"'■'''''  weeds  or  on  ground  .The 
'       3'.%i-'''       e§?s  soon  hatch  and  the 
j^-^^  ',  young  worms  from  them 
' -I  feed  on  the  same  plants  or  al- 
most any  late  crop  till  near- 
i^--  'T\l::;0'ik:ii^f''  )yfull?rown  Inlatefallthey 
V;^  -^  -  i-^'  ^-  .     -'     bury  themselves  deep  in  t  he 
ground  for  protection  durin?  winter.  In  spnny 
they  emerje  and  attack  most  any  youn?  and 
tender  plants  they  find  at  the  surface. 


Young  cabbage    '^-^r,. 
plant  protected  from  ^  : 
cutworms  hy  poisoned 
bait.  The  cutworms    ,  , 
feed  at  night  and  will 
usually  hide  in  the  ground 
or  under  rubbish  before 
they  die. 


PROTECT  YOUR  PLANTS  WaTH 

POISONED  BAIT 

TO  PREPAEE  POISONED  BAIT:  Mix  thoroughly  J4- pound  of  wjiite  arsenitf with  a 
peck  of  dry  bran.  Stir  a  pint  of  cheap  sirup  or  molasseslnto4-to6  quarts  of  water. Use  this 
to  make  up  the  poisoned  bran  into  amash.Let  stand  severalhours  to  allow  the  bran 
to  take  up  the  arsenic.  Other  powdered  arsenicals  maybe  substituted  if  amount  is  doubled 

Late  in  the  day  scatter  the  mash  ^Airj/v  alon?  therowsorao-ound  bases  of  the  plants 
to  be  protected.  KEEP  CHICKENS  AWAY . 

(The  addition  of  chopped  lemons  ororanges  to  this  bait  for  cut'worms  is  sometimes  re- 
commended as  for  grasshoppers  and  may  increase  its  attractiveness) 


Fig.  306, — Bureau  of  Entomology  Chart,  information  regarding  cutworms 

276 


INSECTS  INJURIOUS  TO  POTATOES  AND  TOMATOES     277 

bollworm  (see  pages  108  and  221),  under  which  names  their  habits 
and  hfe  histories  have  been  fully  described. 

Obviously  tomatoes  should  not  be  planted  on  land  which  has 
been  in  corn  or  cotton  infested  by  this  insect  the  previous  year, 
unless  it  has  been  given  thorough  winter  plowing  and  harrowing. 

It  has  seemed  to  the  writer  that  trap  rows  of  sweet  corn  might 
be  used  for  protecting  tomatoes  as  they  are  used  with  cotton,  but 
no  experiments  seem  to  have  been  conducted  which  show  the  prac- 


FiG.  237. — Bollworm  boring  into  green  tomato.     (After  Quaintance  and 
Brues,  U.  S.  Dept.  Agr.) 

ticability  of  the  method.  As  the  young  caterpillars  feed  a  little  on 
the  foliage  before  boring  into  the  fruit,  a  thorough  spraying  with 
arsenate  of  lead,  3  pounds  to  50  gallons,  will  undoubtedly  protect 
the  tomatoes  if  applied  as  soon  as  the  eggs  are  laid,  and  with  one 
or  two  later  applications  at  intervals  of  ten  days,  the  exact  time 
depending  upon  the  latitude  and  season,  as  indicated  by  the  life 
history  (see  page  168). 


CHAPTER  XV 
INSECTS  INJURIOUS  TO  BEANS  AND  PEAS  * 

The  Pea-weevil  f 

The  common  Pea-weevil  occurs  in  almost  all  parts  of  the  world 
where  peas  are  grown,  and  is  the  usual  cause  of  "buggy"  peas.  It 
was  the  cause  of  the  abandonment  of  pea  growing  in  the  central 
Atlantic  States  as  early  as  the  middle  of  the  eighteenth  century. 
It  has  usually  been  regarded  as  a  native  of  North  America,  having 


Fig.  238. — The  pea-weevil  (Bruchus  pisorum.li.):   a,  adult  beetle;   b,  larva; 
c,  pupa — all  enlarged.     (From  Chittenden,  U.  S.  Dept.  Agr.) 

been  introduced  into  Europe.  It  does  but  comparatively  little 
damage  in  more  northern  latitudes  and  for  this  reason  seedsmen 
secure  their  seed  peas  from  Canada  and  northern  Michigan  and 
Wisconsin. 

The  weevil  is  about  one-fifth  inch  long  and  about  one-half 
that  width,  being  the  largest  of  the  pea-  and  bean-feeding  weevils 
in  this  country.  "  Its  ground  color  is  black,  but  it  is  thickly  cov- 
ered with  brown  pubescence,  variegated  with  black  and  white 
markings  as  shown  in  Fig.  238.  The  sides  of  the  thorax  are  notched 
or  toothed,  and  the  abdomen,  which  projects  beyond  the  wing- 
covers,  is  coated  with  whitish  pubescence  and  marked  by  two  black 
spots.  The  hind  thighs  are  thickened  and  each  bears  two  promi- 
nent teeth." 

*  See  F.  H.  Chittenden,  Insects  Injurious  to  Beans  and  Peas,  Yearbook 
U.  S.  Dept.  Agr.  for  1898,  p.  233. 

t  Bruchus  pisorum  Linn.     Family  Bruchidm. 

278 


INSECTS  INJURIOUS  TO  BEANS  AND  PEAS 


279 


Life  History. — The  winter  is  passed  in  the  adult  stage,  the  wee- 
vils making  their  appearance  in  the  fields  when  the  peas  are  in 
blossom.  The  eggs  are  laid  singly  upon  the  surface  of  the  pods, 
attached  by  a  sticky  fluid  which  becomes  white  when  dry.  The 
egg  is  about  one-twentieth  of 


an  inch  long  by  one-third  that 
width,  of  a  yellow  color,  and 
is  shown  in  Fig.  239. 

Upon  hatching,  the  young 
larva  bores  through  the  pod 
and  into  the  seed.  In  this 
stage  the  larva  has  some  very 
small  false  legs  and  two  plates 
and  six  strong  spines  on  the 
thorax,  which  aid  it  in  get- 
ting through  the  pod.  Upon 
entering  the  seed  the  skin  is  Fig.  239.— The  pea-weevil:  a,  egg  on  pod; 


h,  cross  section  of  opening  of  larval  mine; 

c,  young  larva  and  opening  on  inside  of 
pod  by  which  it  has  entered — enlarged 

d,  d,  d,  eggs  on  pod,  slightly  enlarged; 
f,  leg  of  larva;  g,  pro  thoracic  spurious 
processes — more  enlarged.  (After  Chit- 
tenden, U.  S.  Dept.  Agr.) 


shed  and  these  legs,  plates 
and  spines  are  lost.  The 
larva  feeds  upon  the  seed, 
growing  rapidly.  When  full 
grown  it  appears  as  at  b, 
Fig.  238.  It  resembles  a  maggot  in  general  appearance,  being  white, 
except  the  small  mouth-parts,  which  are  brown;  is  fleshy,  nearly 
cylindrical  and  strongly  wrinkled,  with  three  pairs  of  very 
short  stubby  legs.  It  is  about  one-fourth  an  inch  long  and  half 
as  broad.  Before  its  final  molt  the  larva  eats  a  round  hole  in  the 
pea,  leaving  but  a  thin  membrane  as  a  covering.  It  then  lines  the 
inside  of  the  pea  with  a  glue-like  substance,  and  within  this  cell 
transforms  to  the  pupa. 

The  pupa  is  white,  showing  the  notches  at  the  sides  of  the 
thorax,  but  otherwise  is  not  dissimilar  from  many  weevil  pupse. 
The  length  of  the  pupal  stage  varies  from  nine  to  seventeen  or 
more  days.  In  more  southern  latitudes  a  large  part  of  the  beetles 
leave  the  seed  in  August,  but  in  the  North  they  all  remain  in  the 
seed  over  winter,  and  are  planted  with  the  seed.  There  is  but  one 
generation  a  year  and  this  species  does  not  breed  in  dry  peas. 

Injury. — Dr.  James  Fletcher  has  stated  that  this  pest  is  now 
doing  over  $1,000,000  damage  in  Ontario  alone  annually,  and  that 


280        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

the  growing  of  peas  has  been  abandoned  in  considerable  areas  of 
that  province.  In  large  peas  about  one-sixth  of  the  food  content 
is  destroyed,  while  in  smaller  varieties  fully  one-half.  Not  only 
this,  but  in  eating  canned  green  peas  one  frequently  devours  sev- 
eral small  larvae  in  each  mouthful,  unawares,  as  but  a  small  dark 
speck  indicates  their  presence  in  the  green  pea.  In  the  dry  seed 
the  holes  made  by  the  larvae  can  be  seen.  But  12  to  18  per  cent  of 
infested  seed  will  produce  plants,  which  are  later  in  developing  and 
do  not  yield  as  well  as  those  unaffected. 

Enemies. — The  Baltimore  oriole  has  been  recorded  as  feeding 
on  the  grubs  by  splitting  open  the  pods,  and  the  crow  blackbird  is 
said  to  devour  many  of  the  beetles  in  the  spring.  Practically  no 
parasites  or  predaceous  insects  are  known  to  prey  upon  it,  so  that 
it  has  every  opportunity  for  doing  serious  injury. 

Control. — Holding  over  Seed. — One  of  the  best  means  of 
destroying  the  weevils  where  but  a  few  peas  are  concerned  and  cir- 
cumstances will  permit,  is  simply  to  hold  them  over  for  a  season, 
stored  in  a  tight  sack  or  box,  before  planting.  As  the  weevils  will 
not  breed  in  the  dried  peas  they  die  in  the  sack  and  are  thus  caught. 
Peas  should  always  be  bagged  up  and  sacks  tied  immediately  after 
threshing. 

Late  Planting. — Comparative  immunity  from  injury  is  claimed 
by  some  growers  for  late-planted  peas.  Dr.  F.  H.  Chittenden  is 
inchned  to  the  belief  that  in  some  localities,  such  as  Washington, 
D.  C,  where  two  crops  can  be  grown  in  a  year,  that  late  planting 
is  all  that  is  necessary  to  secure  sound  seed  stock. 

Treating  with  Kerosene. — The  Canadians  have  found  that 
kerosene  may  be  used  to  destroy  the  weevils.  Dr.  Fletcher  states : 
"  A  remedy  which  has  been  used  by  many  farmers  with  satisfaction 
is  to  drench  the  seed  with  coal  oil,  using  about  a  half  a  gallon  to  the 
barrel,  or  five  bushels  of  peas.  While  applying  the  coal  oil  (kero- 
sene) the  seed  should  be  placed  on  the  floor,  where  it  can  be  shoveled 
over  constantly  to  insure  the  treatment  of  all  the  grain." 

Scalding  Seed. — ''  When  peas  are  found  to  contain  live  weevils 
at  the  time  of  sowing,  these  may  be  destroyed  by  simply  pouring 
them  into  a  pot  of  scalding  water.  The  water  should  be  drained 
off  at  once  or  the  seed  cooled  by  turning  in  cold  water." — Fletcher. 

Heat. — Dr.  Chittenden  states  that  it  has  been  found  that  a  tem- 
perature of  145°  F.  will  kill  the  weevils  in  the  seed  without  injury 
to  the  germinating  property  of  the  seed. 


INSECTS  INJURIOUS  TO  BEANS  AND  PEAS 


281 


Fumigation. — This  is  undoubtedly  the  best  means  of  destroy- 
ing the  "weevils,  and  is  now  coming  into  general  use.  Dr.  Fletcher, 
who  has  made  the  most  thorough  studies  of  practical  methods  for 
controlling  this  pest,  states:  "Fumigation  with  bisulfide  of  car- 
bon is  a  sure  remedy.  When  properly  done,  either  in  specially 
constructed  buildings  known  as  '  bug-houses  '  or  in  any  tight  bin, 
every  weevil  is  surely  killed  if  the  seed  containing  them  is  fumi- 
gated for  forty-eight  hours  with  this  chemical,  using  1  pound  by 
weight  to  every  100  bushels  of  seed,  or,  in  smaller  quantities,  1 
ounce  to  every  100  pounds.  For  the  treatment  of  small  quantities 
of  seed,  particularly  by  farmers,  I  have  found  that  an  ordinary 
coal-oil  barrel  is  very  convenient.  This  will  hold  about  5  bushels, 
or  300  pounds  of  seed,  which  may  be  treated  with  3  ounces  of  bisul- 
fide of  carbon.  Care  must  be  taken  to  close  up  the  top  tightly. 
This  is  best  done  with  a  cap  made  specially  for  the  purpose,  but 
fine  sacks  laid  smoothly  on  the  top,  over  which  boards  are  placed 
with  a  weight  on  them,  will  answer.  Fumigation  with  bisulfide 
of  carbon  is,  I  believe,  the  remedy  most  to  be  relied  upon  in  this 
campaign.  It  is  perfectly  effective,  is  now  regularly  used  by  the 
large  seed  merchants,  and  in  future  will  be  much  more  generally 
used." 

The  Common  Bean-weevil  * 

Throughout  the  United  States  the  common  Bean-weevil  is  the 


Fig.  240. — The  common  bean-weevil  (Bruchus  obtedus  Say):  a,  beetle;  b, 
larva;  c,  pupa — all  greatly  enlarged.  (After  Chittenden,  U.  S.  Dept. 
Agr.) 

principal  enemy  of  the  bean.     The  small,  white,  footless  grubs 
feed  within  the  beans,  both  in  the  field  and  in  storage,  and  trans- 
*  Bruchus  obtedus  Say.     Family  Bruchidcr. 


282        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


form  to  the  common  brown-gray  weevils  which  infest  white  beans. 
In  the  South  its  attacks  are  so  serious  that  it  is  almost  impossible 
to  secure  a  crop  uninfested,  so  thafc  most  of  the  beans  both  for 
seed  and  consumption  come  from  the  North.  Not  until  1870  did 
injury  by  this  insect  attract  attention  in  the  United  States,  but 
now  it  occurs  throughout  our  borders  and  is  practically  cosmopol- 
itan in  its  distribution.  It  is  probably  a  native  of  Central  or 
South  America. 

The  adult  weevil  is  about  one-eighth  of  an  inch  long  and  is  cov- 
ered with  a  fine 
brown-gray  or  olive 
pubescence,  giving  it 
that  color,  while  the 
wing-covers  are  mot- 
tled as  shown  in  Fig. 
240,  a.  It  may  be 
distinguished  from 
the  pea-weevil  by  its 
longer  thorax  and  by 
the  two  small  teeth 
next  to  the  large 
tooth  at  the  tip  of 
Fig.  241. — The  bean-weevil;  a,  side  view  of  beetle;   the  thighs. 

b,  section  of  bean  pod  showing  slit  for  deposition  Life  History In 

of  egg;  c,  part  of  inside  of  pod  showing  egg-mass  •'  ^' 

inserted  through  slit— all  enlarged.     (After  Riley   the  field  the  eggs  are 
and  Chittenden,  U.  S.  Dept.  Agr.)  j^id  upon  or  are  in- 

serted in  the  bean-pod  through  holes  made  by  the  female  or  such 
openings  as  are  caused  by  its  drying  and  splitting  (Fig.  241,  h,  c). 
In  shelled  beans  the  eggs  are  placed  loosely  among  them  or  in  the 
exit  holes  of  the  beetles.  The  young  larva  hatching  from  the  egg 
has  long,  slender  legs,  but  with  the  first  molt  these  are  lost  and 
when  full  grown  it  is  a  fat  grub  as  shown  in  Fig.  240,  b.  The  pupal 
stage  is  passed  in  an  oval  cell  made  by  the  larva  within  the  bean. 
Experiments  have  shown  that  the  eggs  hatch  in  from  five  days  in 
the  hottest  to  twenty  days  in  cooler  weather;  the  larval  stage 
requires  eleven  to  forty-two  days,  and  the  pupal  stage  five  to  eigh- 
teen days.  Thus  the  whole  fife  cycle  will  extend  over  a  period  of 
from  twenty-one  to  eighty  days,  depending  upon  the  season  and 


INSECTS  INJURIOUS  TO  BEANS  AND  PEAS  283 

locality.  Probably  aljout  six  generations  occur  annually  in  the 
District  of  Columbia,  and  a  less  number  farther  north. 

"  Unlike  the  pea-weevil,  a  large  number  of  individuals  will 
develop  in  a  bean,  as  many  as  twenty-eight  having  been  found 
within  a  single  seed.  It  will  thus  be  readily  seen  that  the  first  out- 
door generation  or  any  single  indoor  generation  is  capable  of 
exhausting  seed  and  completely  ruining  it  for  food  or  planting  or 
any  other  practical  purpose,  except  perhaps  as  hog  feed." 

"The  beetles  begin  to  issue  from  beans  in  the  field  in  a  climate 
like  that  of  the  District  of  Columbia  ...  as  early  as  October, 
when  in  the  natural  course  of  events  the  eggs  for  a  new  brood 
would  be  deposited  in  such  pods  as  had  cracked  open,  so  as  to 
expose  the  seeds  within." 

"  Weevilly  "  seed  should  never  be  planted,  as  but  a  small  per 
cent  of  it  will  germinate  and  the  vitality  of  that  germinating  is 
deficient.  Professor  Popenoe  showed  in  experiments  at  Manhattan, 
Kan.,  that  only  50  per  cent  of  the  infested  seed  used  germinated, 
that  only  30  per  cent  could  have  grown  further,  and  that  even 
these  would  have  produced  plants  of  little  vigor  or  productive- 
ness.    (Quotations  and  facts  from  Chittenden,  I.e.) 

Remedies. — No  methods  are  known  of  preventing  injury  in  the 
"field,  and  all  remedial  measures  must  be  applied  to  the  insects  in 
the  stored  seed.  As  this  species  breeds  in  the  stored  seed,  it  is  use- 
less to  hold  it  over  as  for  the  pea-weevil,  and  the  quicker  infested 
seed  is  treated  the  better.  Either  heat,  or  better,  fumigation,  as 
described  for  the  pea-weevil,  should  be  used.  When  ready  to  plant, 
seed  should  be  thrown  lightly  into  water,  when  that  badly  infested 
will  float  and  can  be  separated  and  destroyed. 

Professor  Geo.  A.  Dean,  of  the  Kansas  Experiment  Station, 
states  that  beans  can  be  protected  from  injury  and  the  weevils 
in  them  killed,  simply  by  storing  them  in  air-slaked  lime.  The 
lime  is  poured  over  the  beans  in  the  container  and  shaken  down 
until  the  beans  are  entirely  covered.  We  have  tested  the  method 
and  secured  perfect  results.  This  is  by  far  the  most  convenient 
method  for  handling  small  quantities  of  beans  and  peas,  es- 
pecially for  those  intended  for  seed.  They  should  be  kept  in  a 
dry  place. 


284      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Fig.  242. — The  cow-pea  weevil  (Bruchus  chi- 
nensis  L.):  a,  adult  male;  b,  egg;  c,  young 
larva;  d,  front  view  of  head  of  same;  e,  thor- 
acic leg  of  same; — a,  much  enlarged;  b,  e, 
more  enlarged.  (After  Chittenden,  U.  S. 
Dept.  Agr.) 


Other  Bean- weevils 

The  Cow-pea  weevil* — This  species  may  be  readily  recognized 
by  the  two  large,  raised  white  lobes  at  the  base  of  the  thorax  and 

the  strongly  pectinate 
antennae  of  the  male  as 
shown  in  Fig.  242,  a.  The 
cow-pea  is  the  favorite 
food-plant  of  this  and  the 
following  species,  but  peas 
and  various  sorts  of  beans 
are  also  attacked.  This 
species  is  a  southern  form, 
but  seems  to  be  spreading, 
incident  to  the  more  wide- 
spread growth  of  the  cow- 
pea.  Like  the  common 
bean-weevil  it  is  practically  cosmopolitan  in  its  distribution,  but 
is  most  injurious  in  tropical  regions.  The  life  history  and  remedial 
measures  are  practically  the  same  as  for  the  common  bean-weevil. 
The  Four-Spotted  Bean-weevil. — fThe  wing  covers  of  this  species 
are  covered  with  gray  -r  a* 

and  white  pubescence  -^^^  

and  four  darker  spots 
from  which  the  spe- 
cies is  named.  It  is 
more  slender  than  the 
preceding  species  and 
the  antennae  of  the 
male  are  not  pecti- 
nate. The  markings 
are  quite  variable, 
but  the  most  com- 
mon form  is  that  shown  in  Fig.  244.  This  is  an  exotic  species  oc- 
curring from  Mexico  to  Brazil  and  in  ihe  Mediterranean  countries. 
In  1885  it  was  found  at  the  Atlanta  Cotton  Exposition  in  black- 
eyed  beans  from  Texas,  and  has  since  become  acclimated  as  far 

north  as  Iowa.    It  seems  to  breed  more  readily  in  fresh  and  slightly 
*  Bruchus  chinensis  Linn. 
I  Bruchus  quadrimaculatus  Fab. 


Fig.  243. — The  four-spotted  bean-weevil:  a,  beetle; 
6,  1  a  r  V  a  ;  c,  pupa — all  enlarged.  (After  Chit- 
tenden, U.  S.  Dept.  Agr.) 


INSECTS  INJURIOUS  TO  BEANS  AND  PEAS 


285 


moist  seed  and,  like  the  preceding  species,  its  work  in  stored  beans 
seems  to  cause  decomposition  and  a  consequent  rise  of  temperature. 
The  life  history  and  remedial  measures  are  similar  to  those  of  the 
bean-weevil. 

The  European  Bean- 
weevil*  was  imported 
into  New  York  and 
New  Jersey  in  1870,.  at 
the  Columbian  Ex- 
position at  Chicago  in 
1893,  and  has  been  ob- 
served at  College  Sta- 
tion, Texas,  but  does 
not  seem  to  have  be- 
come  established  in 
this  country.  It  close- 
ly resembles  the  pea- 
weevil  in  appearance 
and  life  history. 


Fig.  244. — ^The  four-spotted  bean-weevil :  a,  cow- 
pea,  showing  holes  made  by  weevils  in  their 
escape  from  seed,  also  eggs  deposited  on  surface; 
h,  egg;  c,  young  larva;  d,  head  of  same;  e,  proth- 
oracic  leg;/,  spine  above  spiracle  of  first  abdom- 
inal segment — a,  twice  natural  size;  h,  f,  greatly 
enlarged.    (After  Chittenden,  U.  S.  Dept.  Agr.) 


The  Bean  Leaf-beetle  f 

Small  yellowish  or  reddish  beetles,  marked  with  black,  as 
shown  in  Fig.  245,  and  from  one-seventh  to  one-fifth  inch 
long,  are  often  found  eating  the  foliage  of  beans,  and  are  commonly 
known  as  Bean  Leaf-beetles.  The  species  occurs  throughout  the 
United  States  east  of  the  Rockies,  but  has  been  chiefly  injurious 
in  the  Middle  and  Southern  States.  Besides  beans,  the  beetles 
feed  upon  cow-peas  and  various  native  plants  such  as  beggar- 
weed  or  tickseed,  tick  trefoil  (Meibomia),  bush-clover  (Lespedeza) , 
and  hog-peanut  (Falcata).  They  usually  become  quite  numerous 
before  they  are  observed,  for  during  most  of  the  day  they  rest  or 
feed  on  the  under  sides  of  the  leaves.  They  are  sluggish  and 
seldom  fly,  and  when  disturbed  often  drop  to  the  ground,  though 
they  soon  crawl  back  to  the  plant.  Large  round  holes  are  eaten 
in  the  foliage  until  finally  nothing  but  the  veins  and  midrib  of  a 


*  Bruchus  rufimanus  Boh. 
t  Ceratoma  trifurcata  Forst. 


Family  Chrysomelidoe. 


286       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


leaf  is  left,  the  manner  of  defoliation  being  quite  characteristic 
of  this  species.  Low-growing  and  dwarf  varieties  are  worse  injured, 
as  pole  beans  put  out  new  leaves  after  the  injury  has  stopped, 
Life  History. — The  adult  beetles  hibernate  in  or  near  the  bean, 
fields  and  emerge  from  April  to  June  according  to  the  latitude. 
Minute  orange-colored  eggs  are  laid  near  the  stem  of  the  plant- 
just  below  the  surface  of  the  soil,  in  clusters  of  six  to  ten  or  more, 

and  hatch  in  from 
.  five  t  o  eight  days. 
The  young  larvae  feed 
upon  the  stem  and 
roots,  becoming  full 
grown  in  six  or  seven 
weeks.  When  grown 
the  larva  is  about 
three-tenths  an  inch 
long,  about  one-eight 
as  wide,  cylindrical, 
milk-white  in  color, 
with  dark  head  and 
anal    segment,    a  s 

Fig.  245.— The  bean  leaf-beetle  (Ceratoma  trifurcata  shown  enlarged  six 
Forst.):  o,  adult  beetle;  6,  pupa;  c,  larva;  c^>  side  j-j^j^gg  jjj  Fig.  245. 
view  anal  segment  of  larva;   e,  leg  of  same;  /,  egg  '  * 

— a,  b,  c,  enlarged  about  six  times;  d,  e,  f,  more    J- he  pupa  (rig.  ^45, 
enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.)       ^_)  jg  p^j-g  white,  and 

from  it  the  beetle  emerges  in  five  to  eight  days.  Thus,  in  the  Dis- 
trict of  Columbia,  the  whole  life  cycle  requires  six  to  nine  weeks, 
depending  upon  heat  and  moisture.  In  the  North  there  is  prob- 
ably but  one  generation  a  year;  in  Maryland  and  Virginia  one 
generation  develops  in  July  and  another  in  September;  while  in 
the  Gulf  States  there  are  probably  three  generations,  as  beetles 
are  numerous  in  October. 

Remedies. — Spraying  with  arsenical  poisons  as  for  the  bean 
ladybird  is  the  most  effectual  means  of  controlling  the  pest  when 
abundant,  but  they  should  be  applied  early  to  avoid  the  poison 
on  beans  to  be  eaten  green.  Owing  to  the  sluggishness  of  the 
beetles  they  may  be  handpicked  in  small  gardens.     Clean  culture 


INSECTS  INJURIOUS  TO  BEANS  AND  PEAS 


287 


and  careful  weeding  of  native  food-plants  such  as  tick-trefoil  and 
bush-clover,   near    cultivated    crops  are 
most  important. 

The  Bean  Ladybird  * 

The  Bean  Ladybird  is  the  most 
serious  enemy  of  beans  in  Colorado, 
New  Mexico,  Arizona,  and  Western 
Kansas,  whence  it  migrated  from 
Mexico.  It  is  an  interesting  insect  in 
that  only  two  other  native  species  of 
this  family  of  beetles  {Coccinellidoe)  feed 
upon  vegetation,  the  normal  food  of  the 
family  being  plant-lice,  scale  insects,  and 
soft-bodied  larvae. 

Professor  C.  P.  Gillettef  describes  it  as 
follows : 

"  The  beetle  (Fig.  246,  A)  is  oval  in 
outline,  nearly  one-third  an  inch  in 
length  by  one-fifth  an  inch  in  breadth, 
of  a  light  yellow  to  a  yellowish-brown 
color  and  has  eight  small  black  spots  on 
each  wing-cover.  The  mature  larva  is 
about  the  same  length  as  the  beetle,  is 
of  light  yellow  color  and  is  covered  with 
stout  branched  spines  that  are  black  at 
their  tips,  a  larva  being  shown  at  C, 
Fig.  246.  The  larva  when  fully  grown 
fastens  the  posterior  end  of  its  body  to 
the  under  side  of  a  leaf  and  then  in  a 
few  days  sheds  its  outer  skin  containing 
the  spines  and  changes  to  the  pupa  state 

(Fig.   246,  B).      From  these  pupae  the  Fig.  246— The  bean  lady, 
beetles  appear  a  few  days  later.     They 
live  over  winter,  and   appear   about   as 
soon  as  the  beans  are  up  in  the  garden  or 
field  and  begin  to  feed  upon  the  leaves. 


bird  (Epilachna  varivestis 
Mills.):  a,  adult  beetle; 
h,  pupa;  c,  larva;  d,  bean 
pod  showing  injury.  (After 
Gillette,  Colo.  Agr.  Exp. 
Sta.) 


*  Epilachna  varivestis  Muls.     Family  Coccinellidce. 
t  Bulletin  19,  Colo.  Agr.  Exp.  Sta.,  p.  25. 


288        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

on  the  under  side  of  which  they  deposit  their  j^ellowish-brown 
eggs  in  large  clusters  after  the  manner  of  the  'Colorado  potato 
beetle.'  The  spiny  little  larvae  that  hatch  from  these  eggs 
remain  on  the  under  side  of  the  leaves,  which  they  skeletonize  in 
feeding.  The  beetles  eat  through  the  veins  of  the  leaves  and  do 
not  skeletonize  them.  They  also  eat  into  and  destroy  the  green 
pods  as  shown  in  Fig.  246,  D.  There  is  also  one  brood  of  this 
insect  in  a  season. 

Control. — Paris  green  dusted  upon  the  plants  diluted  with 
100  parts  of  air-slaked  lime  or  flour  is  recommended,  or  it  may  be 
applied  with  Bordeaux  mixture,  1  pound  to  200  gallons,  but  much 
care  must  be  used  not  to  burn  the  foliage,  which  seems  to  be  very 
susceptible  to  the  arsenic.  Arsenate  of  lead  applied  as  a  dust, 
with  or  without  a  carrier,  or  as  a  spray  at  from  three  to  five  pounds 
paste  to  100  gallons  of  water  is'  much  more  safe  and  is  now  more 
generally  used  for  that  reason.  In  spraying,  an  underspray 
nozzle  must  be  used  to  reach  under  the  leaves.  Dilute  kerosene 
emulsion  will  kill  the  larvae,  but  must  also  be  used  with  caution 
to  avoid  injury  to  the  plant.  Whaleoil  soap  might  be  as  effective 
and  less  injurious  to  the  plant.  Upon  small  gardens  handpicking 
of  the  adult  beetles  as  soon  as  they  appear  in  the  spring  will  prob- 
ably be  the  surest  means  of  combating  them.  Cleaning  up  the 
old  patch  and  plowing  it  under  will  doubtless  aid  in  preventing 
successful  hibernation. 

Blister-beetles 

Several  species  of  elongate,  grayish,  black  or  bright  green 
blister-beetles  feed  in  large  numbers  upon  bean  foliage.  The 
general  life  history,  habits,  and  remedies  have  been  already 
described.     (See  pages  104.  270.) 

The  Ash-gray  Blister-beetle* — This  is  the  most  common  species 
affecting  beans  in  the  East  and  westward  to  Kansas  and  Nebraska. 
The  beetle  is  a  uniform  ash-gray  color  and  of  the  form  shown  in 
Fig.  247.  The  beetles  attack  this  and  other  legumes  in  immense 
swarms,  riddling  the  foliage  in  a  few  days  if  not  checked,  and 
appear  from  the  middle  of  June  to  the  middle  of  July. 

NuttaU's  Blister-beetle.] — This  species  occurs  from  the  Mis- 

issippi  west  to  the  Rockies,  through  the  region  of  the  Missouri 

*  Macrobasis  unicolor  Kby. 
t  Cantharis  nuttalli  Say. 


INSECTS  INJURIOUS  TO  BEANS  AND  PEAS 


289 


Valley,  and  north  to  the  Northwest  Territories,  where  it  seems  to 
be  particularly  destructive  to  beans,  though  affecting  many 
garden  vegetables.  The  life  history  is  not  known,  but  is  probably 
similar  to  that  of  other  species,  as  the  beetles  appear  about  July  1st 
in  years  following  severe  outbreaks  of  grasshoppers.  Owing  to 
the  rapidity  with  which  this  species  works  and  the  large  numbers, 


Fig.  247. — The  ash-gray  blister-beetle  Fig.     248.— Nuttall's     blister-beetle 

(Macrobasis  unicolor  Kby.) :  female  {Cantharis    nuttalli    Say.) :    female 

beetle  at  right,  twice  natural  size;  beetle,  enlarged  one-third.     (After 

male  antenna  at  left,  greatly  en-  Chittenden,  U.  S.  Dept.  Agr.) 
larged.     (After  Chittenden,  U.  S. 
Dept.  Agr.) 

poisons  will  be  of  Httle  avail  and  mechanical  measures  must  be 
employed  for  their  destruction. 
Control. — See  page  271, 

The  Bean-aphis  * 

**  Crowded  together  in  clusters  upon  the  top  of  the  stalks 
and  under  side  of  the  leaves  of  the  English  bean,  the  poppy, 
dahlia,  and  several  other  plants,  may  be  found  a  small  black  plant- 
louse  with  pale  shanks,  and  a  row  of  mealy  white  spots  along  each 
side  of  the  back." — Fitch. 

This  is  an  old  European  pest  of  the  bean,  where  it  is  known 
the  black  dolphin,  collier,  and  black  fly,  and  has  sometimes 
caused  the  entire  destruction  of  a  crop.  In  the  United  States 
it  probably  occurs  wherever  beans  are  grown,  having  been  reported 
from  New  York,  Illinois,  Iowa,  Minnesota  and  Colorado.  The 
species  is  probably  best  known  as  affecting  various  species  of 

*  Aphis  rumicis  Linn.     Family  AphididoB. 


290      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

clock,  upon  the  leaves  of  which  it  occurs  commonly  in  large  num- 
bers. Shepherd's  purse,  pigweed,  the  "  burning  bush  "(Euony- 
mus  europoeus  and  atropurpurus) ,  and  the  snowball  bush  are  also 
commonly  infested. 

Life  History. — The  life  history  was  first  described  most  inter- 
estingly by  Dr.  Fitch  in  his  13th  Report*  and  has  since  been 
confirmed  by  Osborne  and  Sirrine.f  The  eggs  are  laid  in  the  fall 
around  the  buds  of  the  wahoo  or  "  burning  bush  "  (Euonymus 
atropurpurus),  and  possibly  upon  the  snowball.  The  first  gen- 
eration or  two  multiply  upon  these  plants  and  then  spread  to 
common  weeds  such  as  shepherd's  purse,  pigweed,  dock,  etc., 
during  the  latter  part  of  May  and  early  June,  from  which  they 
again  migrate  to  beans  when  that  crop  is  available.  During 
the  summer  the  aphids  multiply  upon  these  food-plants  vivipar- 
ously,  i.  e.,  by  giving  birth  to  live  young, all  being  females,  as  is  the 
rule  with  aphids;  but  about  the  middle  of  September,  in  Iowa, 
winged  males  and  females  migrate  back  to  the  wahoo. 

Description. — The  wingless  females  are  about  one-tenth  an 
inch  long,  pear-shaped,  sooty  black,  frequently  marked  with 
pruinose  whitish  dots  along  each  side  of  the  back.  The  anteimse 
are  about  half  the  length  of  the  body,  yellowish-white,  except 
toward  the  tips  and  the  two  basal  segments,  which  are  black. 
Honey  tubes  short,  scarcely  half  as  long  as  from  their  bases  to 
tip  of  abdomen.     Tail  half  as  long  as  the  honey  tubes. 

The  winged  females  are  glossy-black,  one-twelfth  an  inch 
long  to  the  tip  of  the  abdomen  and  twice  that  length  to  the  tip 
of  the  closed  wings.  The  abdomen  lacks  the  white  spots  of  the 
wingless  females  and  pupae.  Legs  are  black,  except  shanks, 
which  are  whitish  with  dark  tips.  Otherwise  the  winged  fca-m 
resembles  quite  closely  the  wingless  form.  The  black  color 
and  white  spots  on  the  abdomen  of  the  wingless  females  and 
pupse  will  readily  distinguish  the  species  from  other  aphids  on 
beans. 

Control. — Spraying  with  dilute  kerosene  emulsion  has  proven 
the  best  means  of  combating  the  pest  according  to  Osborn  and 
Sirrine,  diluting  the  stock  solution  fifteen  times,  or  so  the  spray- 
ing mixture  will  contain  about  5  per  cent  of  kerosene.     It  seems 

*  Fitch,  13th  Report  on  the  Noxious,  Beneficial  and  other  Insects  of  the 
State  of  New  York,  Trans.  N.  Y.  State  Agr.  Soc,  18G9,  p.  495. 

t  Osborn  and  Sirrine,  Bulletin  23,  Iowa  Agr.  Exp.  Sta.,  p.  901,  1894. 


INSECTS  INJURIOUS  TO  BEANS  AND  PEAS 


291 


that  the  fohage  of  the  bean  is  quite  susceptible  to  injury  from  any 
free  kerosene,  and  prol)ably  whalcoil  soap  1  pound  to  5  or  6  gal- 
lons, would  prove  safer  and  equally  efficient.  As  it  is  frequently 
necessary  to  spray  beans  with  Bordeaux  mixture  or  other  fun- 
gicides for  fungous  diseases,  the  whaleoil  soap  might  be  readily 
sprayed  at  the  same  time. 

Of  late  years  tobacco  extracts  have  largely  supplanted  the  oil 
and  soap  emulsions  and  it  is  probable  that  they  will  be  more 
satisfactory  in  most  places  as  a  treatment  for  this  insect. 


The  Seed-com  Maggot  * 

This  insect  has  been  termed  the  Seed-corn  Maggot  on  account 
of  its  frequent  injuries  to  early  seed-corn,  but  in  recent  years  it 
has  often  seriously  injured  the  seeds  of  beans  and  peas,  on  account 
of  which  it  has  been  termed  the   "  bean-fly,"   while  cabbage, 


Fig.  249. — Seed-corn  maggot  {Pegomyia  fusciceps):  a,  male  fly,  dorsal  view; 
b,  female,  lateral  view;  c,  head  of  female  from  above;  d,  larva,  from  side; 
e,  anal  segment  of  larva;  /,  anal  spiracles;  g,  cephalic  spiracles;  h,  pupa- 
rium — all  much  enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

turnip,  radish,  onions,  beets  and  seed  potatoes  are  among  its 
other  food-plants. 

The  species  is  of  European  origin,  and  was  first  noted  in  this 
country  by  Dr.  Asa  Fitch,  in  1856.  Since  then  it  has  become 
distributed  throughout  the  United  States  from  Minnesota  to 
Texas  and  eastward. 

*  Pegomyia  fusciceps  Zett.     Family  Anthomyiidce. 


292       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  adult  flies  closely  resemble  the  root-maggots  affecting 
the  cabbage  and  onion  and  are  about  one-fifth  an  inch  long. 
The  male  may  be  distinguished  from  nearly  related  species  by  a 
row  of  nearly  equal,  short  bristles  on  the  inner  side  of  the  hind 
tibise  or  shanks. 

The  life  history  of  the  species  has  not  been  carefully  observed, 
but  is  probably  similar  to  that  of  other  root-maggots.  The 
flies  deposit  their  eggs  either  upon  the  young  seedling  just  as  it 
appears  above  ground,  or  probably  more  often  on  the  seed  itself. 
Injury  is  called  to  attention  by  the  seed  failing  to  germinate, 
which,  when  examined,  is  found  to  contain  one  or  more  small 
white  maggots,  which  have  destroyed  the  germ  or  the  young 
seedling.  Thus  in  1895,  large  areas  of  beans  were  destroyed  in 
Minnesota.* 

The  maggots  are  about  one-fourth  an  inch  long,  slightly 
smaller  than  the  onion-maggot,  from  which  they  may  be  dis- 
tinguished by  the  tubercles  of  the  anal  segment. 

Control. — It  has  been  noted  that  injury  often  occurs  where 
stable  manure  has  been  turned  under,  and  it  may  be  possible 
that  the  flies  are  attracted  to  it  to  oviposit  or  that  they  are 
attracted  by  decaying  seed.  In  preventing  attacks  of  root- 
maggots  it  would  seem  advisable  to  apply  stable  manure  the 
previous  fall  so  that  it  may  become  well  rotted  and  incorporated 
into  the  soil  before  seeding.  Rolling  the  seed-bed  after  planting 
might  also  be  of  value  in  preventing  the  access  of  the  flies  to  the 
seed. 

Applications   of   commercial   fertilizers   which   will   insure    a 

quick  growth  of  the  seedling  are  advisable.  The  use  of  carbolic  acid 

emulsion  and  sand  and  kerosene  upon  the  surface  of  the  seed-bed 

after  planting  and  as  the  seedlings  are  appearing,   as  advised 

for  the  cabbage  root-maggot,  will  also  be  of  value.       Inasmuch 

as  the  injury  is  sporadic  and  affects  the  seed  before  it  can  be 

readily  detected,  reliance  must  be  placed  chiefly  upon  general 

cultural  methods  as  outlined  above  and  others  which  a  better 

knowledge  of  the  life  history  of  the  pest  will  undoubtedly  suggest. 

*  See  Lugger,  Bulletin  43,  Minn.  Agr.  Exp.  Sta.,  p.  207  (1st  Rept.  Minn. 
State  Entomologist).  See  Circular  63,  and  Bulletin  33,  p.  84,  Bureau  of 
Entomology,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  BEANS  AND  PEAS 


293 


The  Pea-aphis  * 

Large  green  plant-lice  often  become  so  abundant  on  the  foliage 
and  pods  of  garden-peas  as  to  kill  the  plants.  Prior  to  1899  the 
pea-aphis  had  not  been  a  serious  pest  in  this  country,  but  during 
that  and  the  following  season  it  caused  a  loss  of  several  million 
dollars  to  pea-growers  on  the  Atlantic  coast  from  North  Carolina  to 
Nova  Scotia  and  as  far  west  as  Wisconsin,  especially  where  peas 
were  extensively  grown 
for  canning.  During 
1901  injury  was  by  no 
means  as  serious,  and  has 
materially  decreased 
since  then,  though  spo- 
radic injury  occurs 
almost  every  year  in  some 
section.  General  injury 
occurs  only  periodically 
for  reasons  mentioned  be- 
low. The  pest  seems  to 
occur  throughout  the 
States  east  of  the  100th 
meridian  and  possibly 
farther  west.  It  is  an  old 
enemy  of  peas  in  Eng- 
land, where  it  destroyed 
the  crop  as  long  ago  as 
1810,  and  it  has  long  been 
known  in  Europe  as  an 
enemy  of  peas,  clovers, 
vetches  and  related 
plants. 


Fig.  250. — The  pea-aphis  (Macrosiphum  pisi 
Kalt.):  winged  and  wingless  viviparous  fe- 
males and  young — enlarged. 


Both  wingless  and  winged  aphids  occur  together  throughout 
the  season,  the  latter  predominating  whenever  food  becomes  scarce. 
The  winged  forms  are  from  one-eighth  to  one-seventh  of  an  inch 
long,  with  wings  expanding  two-fifths  of  an  inch.     The  body  is  a 

*  Macrosiphum  pisi  Kalt.  Family  AphididoB.  See  Chittenden,  Circular 
43,  Bureau  of  Ent.,  U.  S.  Dept.  Agr.;  Sanderson,  Bulletin  49,  Del.  Agr.  Exp. 
Sta.;  Folsom,  Bulletin  134,  111.  Agr.  Exp.  Sta. 


294       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


pea-green  color,  light  brownish  between  the  wings  and  on  the  head, 
the  eyes  are  red,  and  the  legs,  antennse  and  honey  tubes  are  yellow- 
ish, tipped  with  black.  The  wingless  females  are  similar  in  size  and 
color,  but  are  much  broader  across  the  abdomen,  and  the  honey 
tubes  are  somewhat  larger.  The  mouth-parts  of  the  pea-aphis  are 
of  the  sucking  type,  and  it  secures  its  food  by  puncturing  and  suck- 
ing up  the  juices  of  the  plant.  The  plant  is  thus  injured  by  the 
large  number  of  aphids  sucking  out  its  juices  and  causing  it  to 
wilt  and  die. 

Life   History. — The   aphids   pass   the   winter   on   clover   and 
vetches,  and  often  increase  upon  clover  so  as  to  do  it  serious 

injury.  Where  peas  are 
available  the  winged 
females  usually  migrate 
to  them  about  the  time 
peas  are  6  or  8  inches 
high,  and  give  birth  to 
live  young,  which  de- 
velop into  wingless  vivi- 
parous females.  These 
females,  as  do  those  of 
subsequent  broods 
throughout  the  summer, 
give  birth  to  live  young, 
and  reproduction  goes 
on  at  a  rapid  rate.  Ac- 
cording to  the  observa- 
tions of  Mr.  R.  L.  Web- 
ster, in  central  Illinois, 
an  aphid  becomes 
grown  about  eleven 
days  after  it  is  born, 
lives  about  twenty-five  days  and  gives  birth  to  about  fifty  young, 
though  under  favorable  conditions  over  one  hundred  are  frequent- 
ly born.  Sixteen  generations  have  been  observed  from  March  23d 
to  October  4th.  Winged  aphids  develop  as  often  as  the  food- 
plant  becomes  overcrowded  and  it  is  necessary  to  migrate  to 
avoid  starvation. 


Fig.  251. — The  pea-aphids  on  stems  of  red  clov- 
er— natural  size.     (After  Folsom.) 


INSECTS  INJURIOUS  TO  BEANS  AND  PEAS  295 

By  midsummer,  with  the  harvesting  of  the  peas,  most  of  the 
aphids  upon  them  have  been  destroyed  by  predaceous  and  para- 
sitic insects  and  disease,  and  they  are  not  observed  during  late  sum- 
mer unless  they  have  been  subsisting  on  clover  throughout  the 
season,  when  they  sometimes  destroy  the  crop  in  August,  as  has 
been  observed  in  Illinois.  In  early  fall  they  often  become  com- 
mon again  on  late  garden  peas,  and  late  in  October  they  migrate 
to  clover.  Fewer  young  are  born  as  the  weather  gets  colder  in 
the  fall,  and  the  aphids  never  become  numerous  enough  to  do  any 
injury  at  that  season.  Late  in  October  and  early  November — in 
the  Middle  States — as  the  aphids  are  migrating  to  clover,  winged 
males  appear,  and  some  of  the  wingless  females  developing  on 
clover  produce  eggs.  The  winged  males  are  similar  in  size  and  color 
to  the  migratory  females,  though  slightly  darker,  and  have  three  or 
four  dark  spots  along  the  sides  of  the  abdomen  and  a  deep  brown 
dash  on  either  side  of  the  back  of  each  abdominal  segment.  The 
oval  eggs  are  about  one-fiftieth  inch  long,  jet  black,  and  are 
deposited  on  the  lower  leaves  or  stems  of  clover,  and  hatch  as  it 
commences  to  grow  in  the  spring.  In  central  Illinois  they  were 
observed  to  hatch  March  23d,  and  the  young  became  full  grown 
and  commenced  reproduction  on  April  5th,  living  until  May  12th. 
In  southern  Maryland  and  farther  south  many  of  the  viviparous 
females  live  over  winter  on  the  clover  and  commence  to  reproduce 
again  in  the  spring,  no  eggs  having  been  observed  in  that  latitude, 
but  in  central  Illinois  and  northward,  the  females  are  probably 
entirely  destroyed  by  the  cold  and  only  the  eggs  survive. 

Natural  Enemies. — From  5  to  10  per  cent  of  the  aphids  are 
normally  destroyed  by  little  wasp-like  flies  of  the  genus  Aphidius 
whose  larvae  live  within  the  aphids.  A  number  of  the  more  com- 
mon ladybird-beetles,*  syrphus-flies, f  and  lace-winged  flies, { 
which  commonly  prey  upon  aphids,  destroy  large  numbers  of  the 
pests,  but  their  work  comes  so  late  in  the  season  that  the  peas  are 
seriously  injured  long  before  the  aphids  are  checked  by  them, 
though  they  might  prevent  a  reappearance  the  next  year. 

The  most  important  enemy  of  the  pea-aphis  is  a  fungous  dis- 
ease (Empusa  aphidis)  which  is  undoubtedly  the  principal  factor 
in  its  natural  control.     The  most  probable  explanation  of  the 

*  YsioiilyCoccinelUdce. 

t  Family  Syrphidce. 

I  Family  Chrysopidce.     Concerning  these  predaceous  insects,  see  Chap.  I. 


296       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

remarkable  outbreak  of  the  pea-aphis  in  1899  and  1900  seems  to  be 
that,  due  to  two  exceptional^  dry  springs,  the  fungus  was  unable 
to  develop,  as  it  propagates  best  in  damp  weather,  and  the  aphids 
increased  unchecked.  Though  occasional  individual  aphids  were 
found  killed  by  the  fungus  early  in  the  season,  not  until  June  11, 
1900,  were  diseased  aphids  found  in  any  quantity,  but  after  that 
so  swiftly  did  the  disease  destroy  them  that  a  week  later  but  few 
aphids  were  to  be  found  and  almost  all  were  diseased.  Probably 
this  fungus  usually  destroys  the  aphids  on  clover  before  they  have 
become  excessively  numerous  or  have  migrated  to  peas. 

Control. — Inasmuch  as  the  aphids  spread  from  peas  to  clover, 
the  latter  crop  should  not  be  planted  near  peas  when  avoidable. 
In  the  spring  the  aphids  should  be  carefully  observed  on  the 
clover  and  if  they  become  excessively  abundant,  the  only  way  to 
prevent  their  migration  to  peas  is  to  plow  under  the  clover  deeply 
and  roll  the  field. 

Highly  fertilized  land  in  which  the  moisture  is  retained  by  fre- 
quent cultivation  very  often  enables  a  crop  to  mature  in  spite  of 
moderate  injury.  Peas  sown  broadcast  or  planted  in  8-inch 
drills  have  been  much  more  seriously  injured  than  those  planted 
in  rows  18  to  30  inches  apart  and  cultivated,  and  those  planted 
close  together  afford  no  opportunity  for  brushing  or  cultivating 
as  described  below. 

Early  varieties  of  peas  have  practically  escaped  injury  where 
late  varieties  have  been  wholly  destroyed,  so  that  it  is  obvious  that 
only  the  earliest  varieties  should  be  grown  where  injury  is 
anticipated. 

Early  in  1900  Professor  W.  G.  Johnson  found  that  when  peas 
were  planted  in  rows  that  the  aphids  could  be  readily  knocked  from 
the  vines  by  means  of  brushing  with  a  branch,  and  that  by  follow- 
ing the  brushes  with  cultivators,  the  aphids  would  be  covered  with 
earth  and  destroyed,  either  by  suffocation  or  by  the  heat  of  the 
soil.  Where  the  air  temperature  is  95°  F.  the  soil  will  be  nearly 
120°,  and  aphids  brushed  onto  it  will  be  actually  roasted  to  death 
in  a  few  minutes.  The  cultivation  should  not  be  repeated  for 
about  three  days,  as  it  requires  about  that  time  for  the  destruction 
of  the  insects  covered  with  earth,  if  it  is  not  hot  enough  to  kill 
them  at  once.  By  this  method  large  areas  of  peas  have  been  saved 
fiom  destruction. 


INSECTS  INJURIOUS  TO  BEANS  AND  PEAS 


297 


Though  the  above  methods  will  destroy  quantities  of  the 
aphids  and  thus  prevent  the  destruction  of  the  crop,  they  do  not 
dislodge  the  young  aphids  in  the  terminals,  and  therefore  cannot 
be  relied  upon  to  prevent  all  injury.  Practical  field  tests  have 
shown  that  this  may  be  done  by  spraying  with  whale-oil  soap,  1 
pound  to  6  gallons  of  water.  In  small  gardens  this  may  be  applied 
by  means  of  bucket  or  knapsack  pumps,  and  on  small  acreages 
with  a  barrel  sprayer  with  a  row-spraying  attachment  having  noz- 
zles arranged  so  that  the  vines  will  be  thoroughly  covered  from 
each  side.  The  spray  must  be  applied  with  considerable  pressure 
so  as  to  force  it  into  the  terminals.  Here  again  nicotine  compounds 
have  largely  displaced  the  soap  and  oil  sprays,  although  soaps 
are  largely  used  in  connection  with  the  nicotine.  Mr.  L.  M. 
Smith  recommends  the  use  of  the  following  formula 

"Black-leaf  40" 10  ounces 

Whale-oil  soap 14  pounds 

Water 50  gallons 

He  also  recommends  that  the  spraying  be  done  on  a  bright 
clear  day  so  as  to  avoid  injury  to  the  vines  from  the  spray  material.  * 

The  Pea-moth  f 

The  Pea-moth  is  an  old  pest  in  Europe,  whence  it  was  imported 
into  Canada,  where  it  has  frequently  done  considerable  mischief. 
It    is    known    to    occur    in    the  ^  _. 

large    pea-growmg    sections    of      8^^^«*-\   /.:^^^^eT 
New    Brunswick,    Nova    Scotia       ^^^^^^^^0^!^^^^^' 
and  Ontario,  where  it  first  at-  ^^^x  "    ^  "  "^^^ 

tracted  attention  near  Toronto  '-^^ia:i^    i^,^  T^^'''^ 

in  1893,  and  was  found  in  the 

pea  growing  section  of  Michigan  ><Tr:f-'''-'^'y'^''''''-^^P^-^^ 

in  1908.     The  wings  of  the  adult         ^^^r^^^^^^^ 
moth    expand     about    one-half      -^^^^^^^^^^^^^^^^ 

an  inch,  the  fore-wings  being  Fig.  252.-The  pea-moth  (5emasm 
"dark,  fuscous  or  dusky,  tinged  nigricana  Steph.):  moth  above, 
with  darker  brown  and  mottled  L^Zaftr (M^r  ChhUd™! 
with  white,"  the  hind-wings  U.  S.  Dept.  Agr.) 
being  a  uniform  fuscous  with  a  rather  long  inner  fringe  of  hairs, 
as  shown  in  Fig.  252. 

The  females  may  be  found  flying  around  pea-blossoms  soon 

*  L.  M.  Smith,  Virginia  Truck  Expt.  Sta.,  Bulletin  for  October,  1914. 
t  Semasia  nigricana  Steph.     Family  Tortricidcp. 


298        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

after  sunset,  and  deposit  one  to  three  eggs  on  young  pods.  The 
caterpillar  hatches  in  about  fourteen  days,  according  to  European 
observations,  and  attacks  the  forming  seed.  Affected  pods  usu- 
ally ripen  early.  The  larva  is  whitish-yellow  with  a  pale  brown  head 
and  thoracic  plate,  and  about  one-half  an  inch  long  when  full 
grown.  With  the  opening  of  the  pod  the  larva  crawls  out  and 
enters  the  earth  where  it  spins  a  very  thin  silken  cocoon.  The 
length  of  the  pupal  stage  and  the  method  of  hibernation  do  not 
seem  to  be  well  established.  Very  early  and  very  late  varieties 
are  but  little  injured. 

Remedies. — This  suggests  one  of  the  best  means  of  handling 
this  pest  to  be  the  growing  of  early  varieties,  such  as  Alaska, 
American  Wonder,  Gregory's  Surprise,  Nott's  Excelsior,  and 
McLean's  Little  Gem.  If  the  crop  is  known  to  be  infested,  clean 
up  the  vines  and  burn  them  as  soon  as  it  is  picked.  Spraying 
with  arsenate  of  lead  will  doubtless  aid  in  the  control  where  in- 
festation is  serious. 


CHAPTER  XVI 


INSECTS  INJURIOUS  TO  BEETS  AND  SPINACH  * 

The  Beet-aphis  f 

This  species  was  first  described  by  Mr.  W.  R,  Doane  in  1900 
and  seems  thus  far  to  have  been  found  only  in  Washington  and 
Oregon.  "  Attention  was  first  called  to  this  pest,"  he  says,t  "  in 
1896,  when  it  was  found  that  a  field  of  two  or  three  acres  of  beets 
was  generally  infested,  a  strip  of  twenty-five  to  a  hundred  yards 
being  so  badly  injured  that  the  beets  were  nearly  all  soft  and 
spongy,  and  the  plants  much  smaller  than  the  average. 

"  It  has  been  even  more  destructive  in  Oregon  than  in  Wash- 
ington, at  least  a  thousand  tons  of  beets  having  been  destroyed  by 
it  in  one  year  in  a  single  valley  devoted  largely  to  beet-culture. 
Like  very    many    other 
beet-insects,  this   species 
infests  also  several  wild 
or  useless  plants. 

"  The  smaller  root- 
lets of  the  beet  are  first 
attacked  by  this  aphis, 
and  if  it  occurs  in  con- 
siderable numbers  these 
are  soon  all  destroyed, 
and  the  leaves  thereupon 
soon  wither,  and  the 
whole  beet  shrivels  and 
becomes  spongy.  This 
wilting  of  the  leaves  will 


Fig.  253. — The  beet-aphis  {Pemphigus  betce 
Doane) :  a,  winged  female ;  h,  wingless  fe- 
male; c,  antenna  of  winged  female.  (After 
Doane.) 


frequently,  in  fact,  be  the  first  thing  to  attract  the  attention  of  the 
beet-grower.     The  actual  injury  to  the  crop  will,  of  course,  depend 

*  See  Forbes  and  Hart,  Bulletin  60,  111.  Agr.  Exp.  Sta.,  and  F.  H.  Chitten- 
den, Bulletin  43,  n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr. 
t  Pemphigus  betce  Doane.     Family  Aphididas. 
t  Bulletin  No.  42,  Wash.  Agr.  Exp.  Sta.  299 


300       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

largely  upon  the  time  when  the  attack  of  the  aphis  is  made.  If  the 
plants  are  small  they  may  be  readily  destroyed,  while  if  they  are 
practically  full  grown  the  loss  of  the  small  rootlets  will  not 
materially  affect  them. 

"  No  sexual  generation  of  this  aphis  has  as  yet  been  discovered 
and  no  eggs  have  been  seen,  viviparous  reproduction  continuing 
throughout  the  year  except  when  the  cold  of  the  winter  tempo- 
rarily suspends  the  physiological  activities  of  the  species.  The 
winged  females,  appearing  from  time  to  time  during  the  summer 
and  fall,  serve  to  distribute  the  species  generally,  new  colonies 
being  started  wherever  these  females  find  lodgment  and  food.  In 
districts  liable  to  injury  by  this  insect  it  seems  inadvisable  that 
beets  should  be  the  first  crop  on  new  land,  or  that  ground  should 

be  continued  in  beets  or  in  any  other 
root-crop  after  the  pest  had  made  its 
appearance  in  the  field." 

Another  plant-louse,  called  the  beet 
root-aphis*,  proved  injurious  to  sugar- 
beets  in  Colorado  in  1903.  They  were 
found  "  quite  generally  distributed  in 
the  beet-fields  in  the  vicinity  of 
Rockyford  and  attacking  the  roots  of 
many  weeds."     What  seemed  to  be  this 

Fig.    254.-Beet   root-aphis  species  was  very  abundant    upon   the 

{Tijchea  brevicornis  Hart) :  roots  of  the  common  garden  purslane,  to 

a,  aphis;  b,  antenna; c,  tar-  i  •  i    •,                      ...              t.-^        -n,     . 

sAs-all  greatly  enlarged,  which  it  was  very  injurious.     Near  Fort 

(After  Garman.)  Collins  a  badly  infested  field  of  sugar- 

beets  was  also  seriously  damaged. 

No  practical  means  for  controlling  these  pests  seems  to  have 
been  recorded,  so  that  in  case  of  injury  the  entomologist  of  the 
State  should  be  consulted. 

White  Grubs,  Wireworms,  and  Cutworms 

Fortunately  for  the  sugar-beet  farmer  the  worst  insect  ene- 
mies of  that  plant  feed  upon  the  tops,  and  very  rarely  do  we  hear 
of  serious  damage  being  done  the  roots.  In  the  East  most  of  the 
damage  to  the  roots  is  done  by  those  familiar  old  farm-thieves,  the 
white  grub,  the  cutworm  and  the  wireworm.      As  a  general  rule 

*  Tychea  brevicornis  Hart. 


INSECTS  INJURIOUS  TO  BEETS  AND  SPINACH 


301 


they  will  be  found  to  be  worse  on  lands  previously  in  sod,  which 
sliould  therefore  be  avoided  when  known  to  be  badly  infested  with 
either  of  these  insects,  as  both  are  difficult  to  fight  after  they  have 
once  commenced  doing  noticeable  injury. 

The  life  histories  and  means  of  control  for  these  pests  will  be 
found  discussed  in  Chapter  VII. 

The  Sugar-beet  Webworm  * 

The  sugar-beet  webworm  is  very  similar  to  the  garden  web- 
worm, and  is  so  named  because  it  has  developed  as  a  serious 


Fig.  255. — The  sugar-beet  webworm  {Loxostege  sticticalis  Linn.):  1,  moth; 
2,  eggs;  3,  4,  larvae;  5,  pupa;  6,  winter  tube  of  larva,  opened  at  a  to 
show  pupa — 1,  3,  4,  5,  enlarged.     (After  Gillette,  Colo.  Agr.  Exp.  Sta.) 

pest  of  the  sugar-beet  in  Kansas,  Nebraska,  and  Colorado.     It 

has  been  noted  as  injuring  tansy  in  Michigan,   and  feeds  on 

*  Loxostege   sticticalis   Linn.      Family   Pyraustidw..     See   C.    P.    Gillette, 
Bulletin  98,  Colo.  Agr.  Exp.  Sta.,  and  references  there  given. 


302       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

cabbage,  onions,  and  alfalfa,  as  well  as  pigweed  (Chenopodium 
album)  and  careless  weed  (Amaranthus)  and  will  probably  feed 
on  many  other  crops.  It  is  a  native  of  western  and  central 
Europe,  and  northern  Asia,  and  was  evidently  introduced  on  the 
Pacific  Coast,  as  it  was  noted  in  Utah  in  1869. 

The  moth  is  larger  than  the  garden  webworm,  having  a  wing 
expanse  of  an  inch,  and  is  a  purplish-brown  color  with  darker 
and  paler  bands  as  shown  in  Fig.  255.  The  full-grown  larva  is 
about  an  inch  long,  of  a  dark  color  with  a  white  stripe  down  the 
back  and  one  along  either  side,  and  marked  with  numerous 
black  and  white  tubercles  as  illustrated. 

Life  History. — The  larvae  hibernate  over  winter  an  inch  or 
two  below  the  surface  of  the  soil  in  long  silken  tubes.  In  spring 
they  pupate  in  these  tubes  and  the  moths  emerge  about  the  middle 
of  May.  The  eggs  are  laid  on  the  foliage  either  singly  or  in  clus- 
ters of  from  three  to  ten,  one  overlapping  another.  The  egg 
is  broadly  oval,  one  twenty-fifth  inch  long,  and  of  a  pale  green 
color.  The  first  generation  of  caterpillars  feed  on  pigweed 
and  alfalfa  in  Colorado  during  June.  A  second  generation  of 
larvae  occurs  about  the  middle  of  July  and  sometimes  injures 
beets,  but  the  third  generation  about  the  middle  of  August  is 
the  one  most  injurious  in  Colorado.  Most  of  these  larvae  hibernate 
over  winter,  but  there  is  a  partial  fourth  generation  in  Colorado. 
The  larvae  defoliate  the  plants,  and  cover  them  with  a  web  the 
same  as  the  native  garden  webworm,  with  which  the  life  history 
seems  to  be  practically  identical. 

Control. — The  same  means  of  control  as  for  the  garden  web- 
worm are  advised. 

The  Beet  Army  Worm  * 

"  This  caterpillar,  which  replaces  the  fall  army  worm  (L. 
frugiperda — see  Chapter  VII)  in  the  Western  States,  differs  from 
it  by  its  more  decidedly  mottled  ground-color,  by  a  row  of  white 
dots  at  the  lower  margin  of  the  lateral  dark  band,  and  by  the 
yellower  color  of  the  light  stripes.  It  is  an  interesting  fact  that 
while  the  preceding  species  was  doing  serious,  unusual,  and  widely 
extended  injury  in  the  Eastern  and  Southern  States  (1899,) 
the  present   one   was  similarly  abundant  in   Colorado,   where, 

*  Laphygma  exigua  Hubn.     Family  Noctuidce. 


INSECTS  INJURIOUS  TO  BEETS  AND  SPINACH 


303 


besides  destroying  many  kinds  of  weeds  and  grasses,  it  com- 
pletely defoliated  thousands  of  acres  of  sugar  beets.  In  some 
cases  where  the  foliage  of  the  beet  did  not  furnish  it  sufficient 
food,  the  root  was  attacked  and  the  upper  surface  was  com- 
pletely gnawed  away. 
Late  plantings,  of 
course,  suffered  most 
severely,  especially 
when  surrounded  by 
newly  broken 
ground.  The  weeds 
most  generally  eaten 
were  pigweed,  salt- 
weed,  wild  sunflower, 
and  Cleome.  Potato, 
pea,  and  apple  leaves 
were  also  devoured. 
These  injuries  oc- 
curred about  the 
middle  of  August,  at 
which  time  the  larvae 
and  pupae  were  abun- 


FiG.  256.— The  beet  army  worm  (Laphygma  exigua 
Hubn.):  a,  moth;  b,  larva,  side  view;  c,  larva, 
back  view;  d,  head  of  larva;  e,  egg  from  above;  /, 
egg  from  side — all  enlarged.  (After  Chittenden, 
U.  S.  Dept.  Agr.) 


dant,  and  a  few  moths  laden  with  eggs  were  noticed." 

This  species  evidently  hibernates  as  a  moth,  and  at  least 
two  broods  of  larvae  may  be  looked  for  each  year,  the  first  about 
June  and  the  second  in  August.  The  species  has  been  reported 
thus  far  from  Colorado  and  California,  but  it  doubtless  has  a 
more  extended  range  in  the  mountain  regions  of  the  far  West. 

"  Professor  Gillette's  field-experiments  showed  that  it  could  be 
destroyed  by  dusting  or  spraying  arsenical  poisons  on  the  leaves." 

Flea-beetles 

Several  species  of  flea-beetles,  chiefly  Systena  toeniaia,  Systena 
hudsonias,  Disonycha  triangularis,  and  Phyllotreta  vittata,  often 
do  considerable  injury  by  gnawing  small  holes  in  the  upper  and 
lower  surfaces  of  the  leaves  of  beets,  giving  them  an  appearance  as 
if  affected  by  leaf-spot,  or  puncturing  them  full  of  small  holes,  and 
thus  stunting  the  growth  of  the  plants. 


304      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Spinach  Flea-beetle  * 

Of  the  many  species  of  flea-beetles  injurious  to  sugar-beets, 
the  spinach  flea-beetle  is  one  of  the  largest  and  most  destructive. 
The  beetle  is  nearly  one-quarter  inch  long,  shining  black,  with 
a  greenish  or  bluish  lustre.  The  prothorax  and  abdomen  are 
red  or  reddish  yellow,  and  the  legs  and  antennae  are  pale  yellowish. 
It  occurs  from  New  England  to  Montana  and  southward  to  the 
Gulf,  and  is  one  of  the  most  common  pests  of  beets  and  spinach, 
while  its  native  food  plants  are  chickweed  and  lambsquarter. 

Life  History. — The  beetles  hibernate  over  winter  and  emerge 
in  the  spring  during  April  and  May.     The  buff  or  orange  eggs  are 

laid  on  end  in  small 
masses,  "  at  the  bases 
of  the  plants  infested, 
on  bits  of  leaf  or  earth, 
or  even  within  the 
earth "  according  to 
Forbes.  The  eggs 
hatch  from  sometime 
in  April  to  early  July, 
according  to  locality. 
The  larvae  usually  feed 
on  the  under  side  of 
the  leaf,  keeping  to- 
gether in  families 
which  migrate  from 
Fig  257.  — The  spinach  flea-beetle  {Disonycha  jgg^f  ^q  jg^f  while 
xan</iometena  Dahn.):  a,  beetle;  6,  egg  mass;  66, 
sculpture  of  egg;   c,  larva;    d,  pupa;   e,  young  young,  and  drop  to  the 

larva;  /,  abdominal  segment  of  same — a,  c,  d,   gj-gund as    do    the 

five  times  natural  size;  6,  more   enlarged;    66,   f 

f,  highly  magnified.     (After  Chittenden,  U.  S.   beetles — W  hen     d  1 S- 
Dept.  Agr.)  turbed.     While  young 

they  merely  gnaw  the  under  surface  of  the  leaf,  but  later  they  eat 
through  and  riddle  it  with  round  holes,  in  which  they  are  aided 
by  the  beetles.  The  full-grown  larva  is  about  one-quarter  inch 
long,  of  a  dull  gray  color,  except  on  red  and  purple  beets,  on 
which  it  assumes  the  color  of  the  plant  attacked,  is  of  a  cylin- 

*  Disonycha  xanthome! oena  Dalm.  Family  Chrysomelidoe.  See  F.  H.  Chit- 
tenden, Bulletin  43,  Bureau  of  Ent.,  U.  S.  Dept.  Agr.,  p.  14;  S.  A.  Forbes, 
21st  Rept.  State  Ent.  of  111.,  p.  116. 


INSECTS  INJURIOUS  TO  BEETS  AND  SPINACH  305 

drical  form,  and  the  segments  are  strongly  marked  by  rows  of 
raised  tubercles,  each  of  which  bears  a  black  hair  at  the  tip.  The 
larvae  become  grown  in  late  June  and  early  July  in  lUinois,  and 
enter  the  earth  to  pupate,  the  beetles  of  the  next  generation 
emerging  about  a  month  after  the  eggs  were  deposited.  The  beetles 
of  the  second  generation  lay  their  eggs  from  July  to  September 
and  the  beetles  mature  before  winter  sets  in.  In  the  District 
of  Columbia,  Chittenden  observes  that  the  first  generation  is  more 
abundant  on  chick-weed  and  the  second  is  injurious  to  beets  and 
spinach. 

Control. — Thoroughly  dusting  or  spraying  the  plants  with 
arsenate  of  lead  will  readily  destroy  the  larvae  and  probably 
most  of  the  beetles.  As  in  combating  all  flea-beetles  the  destruc- 
tion of  the  weeds  upon  which  they  multiply  is  important. 

The  Larger  Beet  Leaf-beetle  * 

One  of  the  principal  pests  of  the  sugar-beet  in  Colorado  and 
adjacent  States  is  a  rather  large  brownish  leaf -beetle  which  with 
its  larvae  destroy  the  foliage  or  so  injure  it  that  the  plant  dies. 
It  is  often  locally  known  as  the  "  alkali  bug  "  from  the  fact  the 
injury  is  mostly  on  alkali  soil  or  land  near  it,  and  *'  french  bug," 
probably  from  the  "  frenching  "  of  the  fohage.  The  beetle  is 
from  one-quarter  to  one-third  inch  long,  and  rather  resembles 
the  elm  leaf-beetle,  varying  from  pale  yellow  to  black,  with  the 
wing-covers  striped  as  shown  in  Fig.  258.  Several  wild  plants, 
including  blites,  Russian  thistle,  and  saltbushf  probably  furnish 
the  normal  food  of  the  insect. 

"  The  beetles  are  gregarious,  '  sometimes  occurring  in  swarms 
Hke  bhster-beetles.'  Their  brownish-gray  eggs  are  deposited 
in  irregular  masses,  usually  on  the  under  sides  of  the  leaves. 
They  hatch  in  about  six  days,  and  their  larvae  or  young  commence 
feeding  at  once,  continuing  for  nine  or  ten  days,  when  they  dig 
their  way  into  the  ground,  a  few  days  later  coming  forth  as  beetles. 
Although  the  beetles  do  much  injury,  the  principal  damage  is 
sometimes  accomplished  by  the  larvae,  hundreds  being  found 
on  a  single  plant,  which  is  either  consumed  or  so  injured  that  it 
shrivels  and  dies.     The  larva,  shown  in  the  illustration,  measures 

*  Monoxia  pundicollis  Say.     Family  Chrysomelidce. 

t  Dondia  americana  and  D.  depressa,  Salsola  tragus,  and  Atriplex  argentea. 


306        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

when  full  grown  about  one-third  of  an  inch  in  length.  The 
general  color  is  nearly  uniform  dark  olive  brown,  the  conspicuous 
piliferous  tubercles  being  pale  yellow,  and  the  head  and  portions 
of  the  legs  black.  The  eggs  are  dull  brownish  gray,  and  the 
surface,  as  seen  through  a  lens,  is  covered  with  septagonal  and 
hexagonal  areas."* 

Control. — Paris  green  diluted  with  flour  and  dusted  over  the 
foliage  has  effectively  controlled  the  pest,  and  probably  any 
thorough  application  of  any  arsenical  either  wet  or  dry  would 
be  effective.  Professor  C.  P.  Gillette f  has  observed  that  the 
beetles  accumulate  on  the  "  mother  "  beets  early  in  the  spring,  so 


Fig.  258. — The  larger  beet  leaf-beetle  {Monoxia  pundicollis  Say):  a,  female 
beetle;  b,  eggs;  c,  d,  larva;  from  above  and  side;  "b,  claw  of  male;  o, 
claw  of  female — all  much  enlarged.    (After  Chittenden,  U.  S.  Dept.  Agr.) 

that  if  a  few  beets  were  left  in  the  ground  over  winter  they  might 
serve  as  trap  plants  for  the  protection  of  the  younger  plants  in 
spring.  As  injury  is  mostly  on  or  near  alkali  ground,  such  soil 
should  be  avoided. 

*  Quoted  from  F.  H.  Chittenden,  Bulletin  43,  Bureau  Ent.,  U.  S.  Dept. 
Agr.,  p.  10. 

t  C.  P.  Gillette,  24th  Report  Colo.  Agr.  Exp.  Sta.  (1902),  pp.  108-111. 


INSECTS  INJURIOUS  TO  BEETS  AND  SPINACH  307 


The  Beet  Leafhopper  * 

Very  serious  loss  to  the  sugar-beet  industry  has  occurred  in 
Colorado,  California  and  Utah  from  a  condition  known  as  "  curly 
leaf  "  or  "  blight."  Investigations  made  by  Professor  E.  D.  Ball 
have  shown  that  the  "  curly  leaf  "  is  undoubtedly  caused  by  the 
presence  of  immense  numbers  of  small  leafhoppers,  from  10  to  100 
often  being  found  on  a  plant  in  badly  infested  fields.  The  curly 
leaf  condition  does  not  seem  to  result,  however,  except  when  the 


O  Fig.  259. — The  sugarbeet  leafhopper  (Eutettix  tenella  Baker):  a,  adult; 
b,  nymph;  /,  eggs — greatly  enlarged;  g,  section  of  beet  stem  showing 
fresh  eggs  in  place;  h,  same  showing  eggs  ready  to  hatch;  i,  old  egg 
scars  on  beet  stems;  j,  small  leaf  of  sugar  beet  showing  characteristic 
"curly-leaf"  condition;  k,  enlarged  section  of  back  of  an  extreme  case 
of  curly-leaf  showing  warty  condition  of  veins.  (After  Ball,  U.  S.  Dept. 
Agr.) 

soil  has  become  dry  and  heated,  and  where  plants  are  shaded  or 

irrigated  the  damage  by  the  leafhoppers  does  not  seem  to  produce 
/^ 

*  Eutettix  tenella  Baker.     See  E.  D.  Ball,  Bulletin  66,  Part  IV,  Bureau 
of  Entomology,  U.  S.  Dept.  Agr.,  and  Bulletin  155,  Utah  Exp.  Sta. 


308         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


the  same  trouble.  Similar  injury  has  been  noted  in  parts  of 
Oregon,  but  not  of  so  serious  a  nature. 

The  beet-leafhopper  is  a  pale  yellowish-green  species  (Fig. 
259),  one-eighth  to  three-sixteenths  inch  long,  and  when  fly- 
ing appears  abnost  white,  so  that  it  is  sometimes  locally  called 
the  "  white  fly." 

Life  History. — The  hibernating  habits  of  the  adults  and  their 
food-plants  in  the  spring  have  not  been  well  determined.     They 


Fig.  260. — "Hopperette"  designed  for  collecting  leafhoppers.     (After  G.  C. 
Davis,  Mich.  Agr.  Exp.  Sta.) 

appear  in  the  beet-fields  late  in  June  and  lay  their  eggs  in  the 
leaf-stems,  the  eggs  hatching  in  about  two  weeks.  The  young 
nymphs  appear  in  July  and  are  very  active,  being  first  found  in  the 
unfolding  leaves  at  the  centre  and  later  spreading  to  all  parts 
of  the  plant.  The  nymphs  are  variously  colored,  but  the  com- 
monest form  is  a  pale  creamy  color  with  a  brown  saddle  on  the 


INSECTS  INJURIOUS  TO  BEETS  AND  SPINACH  309 

middle  of  the  abdomen  and  various  mottlings  on  the  prothorax 
andwingpads.  The  nymphs  become  full  grown  in  from  sixteen 
to  twenty-two  days  and  the  adults  again  become  abundant 
in  August  and  September;  they  evidently  hibernate  as  adults, 
as  no  more  eggs  are  laid  in  the  fall  as  far  as  observed. 

The  characteristics  of  the  "  curly  leaf  "  are  described  by  Dr. 
Ball  as  follows:  "  The  first  symptom  of  '  curly-leaf  '  or  '  blight  * 
of  the  beet  is  a  thickening  of  all  the  smaller  veinlets  of  the  leaf, 
giving  it  a  roughened  appearance  on  the  under  side.  This  is 
followed  by  a  curling  of  the  edge  and  a  final  rolhng  up  of  the  leaf, 
the  upper  surface  always  being  rolled  in.  As  this  progresses  the 
smaller  veinlets  grow  still  larger  and  more  irregular,  knotlike 
swellings  appear  at  frequent  intervals,  and  in  extreme  cases 
little  nipple-like  swellings  appear,  extending  to  a  height  of  nearly 
one-fourth  of  an  inch.  This  will  be  noticed  first  on  a  medium- 
sized  leaf,  gradually  spreading  to  the  younger  ones,  while  at  the 
same  time  the  beet  almost  stops  growing  and  a  large  number  of 
fibrous  roots  are  sent  out.  .  .  .  The  beet  often  continues  in  this 
way  throughout  the  season;  in  bad  cases  it  shrivels  and  dies, 
while  in  a  few  instances  there  is  a  partial  recovery  and  a  new  set 
of  leaves,  though  the  sugar  content  remains  very  low." 

Control. — Practical  measures  of  control  do  not  seem  to  have 
been  very  thoroughly  tested.  With  a  better  knowledge  of  the 
hibernating  habits  of  the  species,  it  may  be  possible  to  reduce  its 
numbers  at  that  time.  After  the  hoppers  have  appeared  in 
numbers  they  must  be  dealt  with  promptly.  "  A  thorough 
spraying  with  kerosene  emulsion  at  a  strength  of  1  part  of  the 
stock  solution  to  5  parts  of  water,  would  destroy  most  of  the 
insects  that  it  hit,  and  by  using  a  drag  in  front  of  the  nozzles  to 
turn  the  leaves  over  and  cause  the  insects  to  jump,  most  of  them 
would  be  reached."  This  would  probably  need  to  be  repeated 
in  about  ten  days.  Hopperdozers  have  often  been  successfully 
used  for  collecting  various  forms  of  leafhoppers.  A  modifica- 
tion of  the  form  used  against  grasshoppers  with  a  couple  of  wings 
extending  out  on  either  side  of  the  row  and  covered  with  a  sticky 
substance  such  as  "  tanglefoot  "  or  that  described  on  page  458 
would  undoubtedly  prove  effective  in  collecting  the  adults, 
particularly  before  the  females  have  laid  their  eggs,  when  they 
are  more  readily  caught.     A  "hopperette  "  designed  by  Professor 


310       INSECT  PESTS  OF  FARM..  GARDEN  AND  ORCHARD 

G.  C.  Davis  for  use  against  leaf  hoppers  on  celery  in  Michigan, 
is  shown  in  Fig.  260,  and  may  be  readily  attached  to  the  frame 
of  a  wheel  hoe.  The  string  across  the  notch  at  A  strikes  the 
plants  and  causes  the  hoppers  to  jump  at  the  right  time.  By 
adding  high  wide  wings  to  either  side  of  this  machine  it  should 
be  well  adapted  for  beets  and  similar  crops. 

However,  even  the  capture  or  killing  of  large  numbers  of  the 
leafhoppers  by  the  means  suggested  will  not,  according  to  Dr. 
Ball,  solve  the  question  of  preventing  the  disease  they  carry, 
since  a  single  puncture  will  often  kill  a  leaf.  Some  means  for  the 
destruction  of  the  hoppers  before  they  reach  the  beet  fields  will 
be  necessary  before  the  disease  can  be  eliminated.  The  outlook 
for  certain  beet-growing  sections  is,  therefore,  still  serious. 


Blister-beetles  * 

Among  those  insects  attacking  the  young  sugar-beets  and 
often  doing  considerable  damage  after  they  have  become  partly 
grown,  few  are  more  widespread  or  do  more  general  injury  than 
the  blister-beetles.  They  have  been  especially  destructive 
in  the  northern  Mississippi  Valley,  where  they  are  usually  worst 
after  a  period  of  unusual  abundance  of  grasshoppers.  Coming 
suddenly  in  a  large  swarm,  they  settle  in  a  field  and  thoroughly 


b  e 

Fia.  261. — The  striped  blister-beetle  (Epicauta  vittata):  a,  female  beetle; 
h,  eggs;  c,  triungulin  larva;  d,  second  or  caraboid  stage;  e,  same  as  / 
doubled  up  as  in  pod;  /,  scarabteoid  stage;  g,  coarctate  larva — all  except 
e  enlarged.     (After  Riley  and  Chittenden,  U.  S.  Dept.  Agr.) 

riddle  the  foliage  with  holes  or  strip  it  bare  before  going  to  another 
field. 

One  of  the  most  common  forms  is  the  striped  blister-beetle, 
or    "old-fashioned    potato-bug"    {Epicauta    vittata),    which    is 

*  Family  Melaidce. 


INSECTS  INJURIOUS  TO  BEETS  AND  SPINACH  311 

shown  in  the  ilkistration,  together  with  the  immature  stages. 
The  ash-gray  bhster  ])cetle  (Macrobasis  unicolor)  is  also  a  common 
form,  shown  in  Fig.  247.  Three  or  four  other  forms  are  common 
throughout  the  country,  but  are  especially  numerous  in  the  West, 
where  grasshoppers  are  more  abundant.  The  reason  for  this  is 
discussed,  along  with  an  outline  of  the  life-history,  in  Chapter  VII 
under  the  heading  of  natural  enemies  of  the  grasshoppers. 

Remedies. — However,  when  they  swarm  into  the  beet-fields, 
potato-  or  garden-patches,  one  cannot  afford  to  allow  them  to 
consume  one  crop  for  the  good  they  may  do  in  saving  another 
from  still  another  insect  scourge.  So  be  ready  for  them  on 
their  first  appearance;  give  the  plants  a  thorough  spraying  with 
1  pound  of  Paris  green  and  1  pound  of  lime  to  125  gallons  of  water. 
It  may  be  well  to  spray  with  Bordeaux  mixture,  which  will 
prevent  various  fungous  diseases,  and  with  which  Paris  green 
can  be  used  much  stronger  without  danger  of  burning  the  foliage; 
or  it  may  be  applied  dry  by  mixing  with  from  ten  to  twenty 
parts  of  flour  or  plaster,  dusting  it  on  in  early  morning,  while  the 
dew  is  still  on  the  plants.  Arsenate  of  lead  sprayed  at  the  rate 
of  3  pounds  to  50  gallons,  or  \ised  as  a  dust,  will  be  equally  effective, 
will  adhere  to  the  foliage  better,  and  will  be  less  likely  to  burn 
the  f  oUage. 

The  Beet  or  Spinach  Leaf-miner  * 

Frequently  beet  and  spinach  leaves  will  be  found  with  tor- 
tuous mines  or  large  blotches  which  have  been  mined  out  by 
small  white  maggots  beneath  the  surface  epidermis.  This  injury 
is  most  commonly  due  to  the  maggot  of  a  small  fly  shown  in 
Fig.  262.  "  The  ground  color  is  gray  with  the  front  of  the  head 
silver  white.  The  body,  including  the  legs,  is  somewhat  sparsely 
covered  with  rather  long  stiff  black  hairs.  When  in  action  the 
body  is  usually  carried  in  a  somewhat  curved  position,  but  when 
extended  measures  nearly  a  quarter  of  an  inch.  The  maggot 
(/■)  is  white,  and  so  nearly  transparent  that  the  contents  of  the 
abdomen  can  be  seen  through  the  posterior  portion." 

Life  History. — "  The  flies,  by  close  observation,  may  be  seen 

in  flight  just  above  the  ground  or  hovering  about  their  different 

food  plants.     The  eggs  are  placed  on  the  lower  surface  of  the 

*  Pegomyia  vicina  Lintn.  See  Chittenden,  I.e.,  from  which  the  quotations 
are  taken. 


312       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


leaves  and  arranged  in  masses  of  from  two  to  five.  When  the 
young  hatch  they  bury  themselves  within  the  leaf  tissue,  con- 
structing a  thread-like  mine  which  they  afterwards  extend  in  a 
curve  or  semicircle.  Transformation  to  pupse  takes  place  in 
most  cases  in  loose  soil,  which  the  maggots  enter  to  only  a  short 
distance,  or  under  fallen  leaves.  Occasionally  maggots  trans- 
form within  a  leaf  if  the  latter  happens  to  rest  on  the  ground. 
Dr.  Howard  states  that  the  eggs  hatch  in  from  three  to  four 


Fig.  262. — The  beet  leaf-miner  {Pegomyia  vicina  Lintn.):  a,  fly;  h,  head  of 
male  fly;  c,  head  of  female;  d,  surface  of  egg  highly  magnified;  e,  egg; 
/,  maggot;  g,  head  of  same;  j,  anal  segment;  k,  anal  spiracles — all 
enlarged.     (After  Howard,  U.  S.  Dept.  Agr.) 

days,  and  the  larval  stage  is  passed  in  seven  or  eight  days,  the 
puparium  or  resting  stage  requiring  from  ten  to  twenty  days. 
"  Injury  appears  to  be  most  frequent  in  late  fall,  but 
even  in  larger  fields  such  a  practice  might  prevent  its  increase 
may  be  due  to  earlier  generations  in  midsummer.  "  In  many 
cases  infestation  can  be  traced  directly  to  the  insect  having 
bred  in  lambsquarters  and  similar  weeds,  which  if  not  destroyed 
by  ordinary  methods  of  cultivation  mature  and  die  during 
October." 


INSECTS  INJURIOUS  TO  BEETS  AND  SPINACH  313 

Control. — Where  this  pest  occurs  in  small  gardens  it  may  be 
controlled  by  picking  and  destroying  the  infested  leaves,  and 
even  in  larger  fields  such  a  practice  might  prevent  its  increase 
and  consequent  injury.  Those  insecticides  which  have  been 
tried  as  remedies  seem  to  have  had  no  effect.  Deep  plowing 
and  thorough  harrowing  of  infested  fields  as  soon  as  the  crop  can 
be  removed  should  greatly  lessen  injury  the  next  year.  As  this 
species  seems  to  prefer  spinach  to  beet,  Dr.  Chittenden  has 
suggested  that  spinach  might  be  used  as  a  trap  crop  in  large 
fields  of  sugar  beets  where  the  injury  warranted  such  a  measure. 


CHAPTER  XVII 

INSECTS  INJURIOUS  TO  CABBAGE  AND  RELATED  CROPS  * 

The  Cabbage  Maggot  f 

Throughout  the  Middle  and  Northern  States  the  cabbage  mag- 
got is  one  of  the  most  destructive  and  most  difficult  to  combat  of 


Fig.  263. — Cabbage  root  infested  with  maggots.     (After  Slingerland.) 

all  the  insects  affecting  cabbage,  cauliflower  and  radishes.     Just 
as  the  plants  are  commencing  to  make  a  good  growth  they  sud- 

*  See  Garman,  "Insects  Injurious  to  Cabbage,"  Bulletin  114,  Ky.  Agr. 
Exp.  Sta. 

t  Phorbia  hrassicoB  Bouche.  Family  AnthomyiidcB.  See  W.  J.  Schoene, 
Bulletins  382  and  419,  N.  Y.  Agr.  Exp.  Sta.,  Journal  of  Economic  Entomol- 
ogy, Vol.  IV,  p.  210. 

314 


INSECTS  INJURIOUS  TO  CABBAGE,  Etc. 


315 


denly  appear  sick,  many  are  found  wilting,  and  soon  die.  Exami- 
nation of  the  roots  shows  that  they  have  been  riddled  by  small, 
white  maggots  as  shown  in  Fig.  263.  Early-planted  cabbage, 
cauliflower  and  radishes  are  particularly  affected,  and  later  in  the 
season  the  maggots  will  be  found  on  turnips  and  wild  mustard. 

These  maggots  are  the  larvae  of  a  small  fly,  resembling  the 
house-fly,  but  distinctly  smaller,  being  only  one-fourth  inch 
long,  with  a  narrower  body  and  proportionately  larger  wings. 
It  is  a  grayish  color  with  three  dark  stripes  on  the  thorax  and  one 


,- 

/' 

/  • 

.J/: 

1 

f  .^v.*:^ 

/ 

\    V 

IN5 

i 

Fig.  264. — The  cabbage  maggot  fly  (Pegomyia  brassicce  Bouche),  female, 
greatly  enlarged.     (After  Slingerland.) 

along  the  middle  of  the  abdomen,  and  the  body  bears  numerous 
stiff  hairs  or  bristles.  The  flies  appear  just  as  early  cabbage  is  set 
out,  in  late  April  and  early  May  in  New  Jersey,  and  in  late  May  in 
southern  Minnesota.  They  do  not  fly  far  and  seem  to  avoid  fields 
which  are  swept  by  the  wind. 

Life  History. — The  females  deposit  their  eggs  on  the  stem  of 
the  plant  or  in  the  soil  near  the  stem,  at  or  just  beneath  the  surface 
of  the  soil,  each  female  laying  some  fifty  eggs.     The  eggs  are  most 


316       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

abundant  in  late  May  and  early  June  in  central  New  York.  Usu- 
ally a  female  lays  but  one  or  two  eggs  on  a  plant  and  prefers  to  lay 
them  in  a  crevice  of  the  stem  or  very  near  it,  for  if  the  young  mag- 
gots have  to  travel  far  to  reach  their  food,  many  will  die  before  find- 
ing it,  and  if  laid  on  hard  soil  the  maggots  will  be  unable  to  pene- 
trate it  to  the  soft  tissue  of  the  root,  as  they  are  unable  to  feed  on 
the  hard  stem  above  ground.  The  eggs  are  about  one  twenty- 
fifth  inch  long,  of  a  pure  white  color,  which  renders  them  easily 
seen  against  the  soil  by  one  familiar  with  them,  and  are  of  the 
shape  shown  in  Fig.  265,  having  a  curious  ridge  along  one  side. 
The  eggs  hatch  in  from  three  to  ten  days,  averaging  five  to  seven. 
The  little  maggots  at  once  commence  rasping  the  surface  of  the 
tender  roots,  gradually  mine  into  them,  and  in  three  or  four  weeks 
have  become  full  grown.  The  grown  maggot  is  one-third  inch 
long,  white  or  yellowish  in  color,  tapering  toward  the  head  and 
obliquely  truncate  at  the  tip  of  the  abdomen.  From 
the  head  a  pair  of  strong,  black,  hook-like,  rasp- 
ing jaws  project  downward,  and  just  back  of  the 
head  on  either  side  is  a  minute,  light  brown,  fanlike 
projection  (Fig.  2676),  or  spiracle,  which  leads  into 
the  breathing  system.     The  oblique  posterior  end 

_,  „_^  ^  is  surrounded  by  twelve  rounded  tubercles  and  in 
Fig.  265. — Egg     .  ,.,.,._. 

of  cabbage  the  centre  are  two  brownish  spiracles  (Fig.   267a). 

maggot,  When  done  feeding  the  larva  burrows  one-half  to 

greatly    en-  . 

larged;   hair  one  inch  under  the  surface  of  the  soil,  and  the  outer 

line  at  center  gj^jjj  gradually  hardens  until  it  forms  a  firm  brown 
of  0    shows    1    1,        „    ,  .  ...        ,  •  ,      ,      , 

natural  size;  shell,  called  a  puparium,    within  which  the  larva 

side^^^/r^  —  transforms  to  a  true  pupa.  Frequently  the  puparia 
(After  Sling-  are  found  in  the  galleries  made  by  the  maggot  or  in 
erland.)  crevices  of  the  roots.     During  the  summer  this  stage 

lasts  about  two  weeks,  but  in  the  fall  most  of  the  insects  remain  in 
this  condition  over  winter.  Thus  the  whole  life  cycle  from  egg  to 
adult  requires  about  six  to  ten  or  twelve  weeks,  according  to  the 
temperature  and  moisture,  and  the  second  generation  of  flies  appear 
in  June  in  New  Jersey  or  by  mid-July  in  southern  Minnesota.  The 
maggots  of  the  second  generation  seem  to  do  but  httle  damage. 
The  life  history  of  the  insect  during  late  summer  has  not  been 
satisfactorily  determined,  but  there  is  undoubtedly  a  third  genera- 
tion and  in  the  South,  possibly  a  fourth,  the  work  of  the  last  gen- 


INSECTS  INJURIOUS  TO  CABBAGE,  Etc. 


317 


eration  being  sometimes  noticed  in  late  cabbage  in  early  fall. 
On  Long  Island,  N.  Y.,  the  larvae  have  been  observed  as  abund- 
ant upon  cabbage  stumps  in  September  and  October,  working 
above  ground,  and  the  adults  and  eggs  have  been  common  around 
the  adventitious  buds.  Rough  estimates  indicate  300  to  1500 
maggots  per  acre  on  these  stumps.  The  puparia  of  the  last,  and 
in  the  North  possibly  some  of  those  of  the  second  generation 
remain  in  the  soil  over  winter,  though  there  is  some  evidence  that 
the  flies  may  also  hibernate  in  the  Middle  States. 

Control. — The  most  effective  measures  of  control  consists  in  cul- 
tural methods  and  preventives,  but  little  practical  success  having 
attended  the  use  of  remedies  to  kill  the  maggots. 

Cultural  Methods. — Inasmuch  as  the  puparia  remain  in  the  soil 
or  in  the  old  roots  or  stumps  over 
winter,  it  is  important  for  this  as 
well  as  other  cabbage  pests  to 
gather  and  destroy  all  the  refuse 
of  the  crop  as  soon  as  possible  and 
then  plow  infested  land  thorough- 
ly in  the  fall.  Mr.  Schoene  has 
shown  that  by  plowing  badly  in- 
fested seed-beds  six  or  seven 
inches  deep  that  only  one-fourth 
as  many  flies  emerged  as  where 
the  soil  was  undisturbed.  A  ro- 
tation of  the  crop  will  be  of  value  fi, 
where  cabbages  are  not  grown  on   3^^  ■■^^  ,t>  -  ^ 

large    acreages.      Cabbage    and   ^'— A'*-''-.^.^r 

,1  -c  i_      1  1       i     Fig.  266. — Eees  of  cabbage  maeeot 

Other  cruciferous  crops  should  not       at  base  of  stalk.     (Photo  by 

be  planted  after  each  other,  as  all       Headlee.) 
are  affected  by  the  same  pests.    It  is  evident  that  if  the  crop  is  plant- 
ed at  some  distance  from  that  of  the  previous  year,  and  as  the  flies 
are  known  to  avoid  wind-swept  fields,  that  many  of  them  will  not 
succeed  in  finding  the  new  planting. 

As  the  maggots  infest  wild  mustard  and  various  similar  weeds, 
these  should  be  destroyed  as  far  as  possible  and  crops  affected  by 
the  maggots  should  not  be  planted  on  or  near  land  badly  infested 
with  such  weeds  if  avoidable.  Wild  mustard  may  be  readily  killed 


318       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

by  spraying  it  while  young  with  iron  sulfate,  2  pounds  to  1 
gallon  of  water. 

Late-planted  cabbage  is  but  slightly  affected  as  compared  with 
that  planted  earlier.  The  earliest  radishes  are  often  quite  free 
from  the  pest,  those  planted  later  and  maturing  just  as  the  flies 
are  abundant  are  badly  injured,  and  the  later  plantings  are  free 
from   injury. 

It  is  evident,  therefore,  that  where  planting  of  the  main  crop 
can  be  delayed  until  after  most  of  the  flies  have  oviposited,  that 
it  will  escape  serious  injury.  Furthermore,  either  cabbage  or  rad- 
ishes may  be  used  as  a  trap  crop,  by  planting  a  few  rows  early 
and  as  soon  as  the  flies  have  laid  their  eggs  on  them,  plowing 

them  under  deeply  and  then  set- 
ting the  main  crop.  All  of  these 
methods  involve  a  familiarity  with 
the  fly  and  its  eggs  which  any  ob- 
servant grower  may  soon  acquire. 
^-weas^  jj-gj^  fertilization  with  a  quickly 

Fig.  267.— Cabbage  maggot,  side  available  fertilizer  will  enable  the 
view,   enlarged,   hair  line  repre- 
sents natural  size;    a,    view    of  plants  to  make  a  rapid  growth  and 

,7racletS°'<;f  head-g?el%  ™"  ^e  profitable  even  it  maggots 

enlarged.  (After  Slingerland.)  do  not  OCCUr. 
Thorough  and  frequent  cultivation  while  the  eggs  are  being 
laid  destroys  many  of  them.  Indeed,  one  of  the  best 'means 
of  control,  which  is  extensively  practiced  by  many  growers,  is  to 
hill  up  the  earth  around  the  young  plants  when  set,  and  as  soon  as 
eggs  are  laid,  pull  the  soil  containing  the  eggs  away  from  the  plant 
into  the  middle  of  the  row,  where  they  or  the  maggots  hatching 
from  them  will  be  killed  by  the  heat.  This  involves  considerable 
hand  work,  but  where  carefully  and  intelligently  followed  is  one 
of  the  surest  means  of  control. 

Preventives. — Where  late  cabbage  is  grown  the  plants  often  be- 
come infested  in  the  seed-bed.  To  avoid  this  the  seed-beds  should 
be  covered  with  cheesecloth.  The  sides  of  the  frame  are  made  of 
12-inch  boards,  across  which  wires  are  stretched  to  prevent  sag- 
ging of  the  cloth,  as  the  whole  must  be  fly-tight.  The  cover 
should  be  removed  a  week  or  ten  days  before  transplanting,  so 
that  the  plants  may  harden.  If  eggs  are  observed  in  the  seed-bed 
during  this  time,  transplant  at  once. 


INSECTS  INJURIOUS  TO  CABBAGE,  Etc. 


319 


The  most  successful  preventive  yet  used  consists  of  a  tarred 
felt  card  placed  around  each  plant  so  as  to  form  a  collar,  lying 
upon  the  surface  of  the  soil  and  thus  preventing  the  fly  from 
depositing  her  eggs.  These  cards  were  originally  devised  by 
Professor  W.  H.  Goff,  of  Wisconsin,  and  have  been  extensively 
used  by  large  growers  in  that  State  for  many  years,  as  well  as 
in  New  York,  and  experiments  in  New  Jersey  and  Minnesota 
have  proven  them  very  satisfactory.  The  cards  should  be  made 
of  one-ply  tarred  felt,  as  ordinary  tarred  paper  or  building  paper 
curls  up  and  is  not  as  effect- 
ive. The  cards  are  made  in 
a  hexagonal  shape,  with  a 
slit  extending  from  one  cor- 
ner to  the  centre,  which  is 
slit  with  a  star-shaped  cut 
to  accommodate  the  stem. 
The  cards  are  cut  with  a  tool 
shown  in  Fig.  269,  which  may 
be  made  by  any  blacksmith, 
and  are  cut  out  in  rows  as 
illustrated,  one  cut  of  the 
tool  making  a  card.  The 
cards  should  be  placed 
around  the  plants  when 
they  are  set.  The  earth 
should  be  smoothed  down 
and   well   firmed    by   the   hand. 


Fig.  268. — Cabbage  roots  destroyed  by  the 
cabbage  maggot.     (After  Slingerland.) 


the  card  then  applied  to  the 
plant,  and  pressed  down  tight  to  the  ground,  so  that  it  fits  snugly 
around  the  stem  and  the  edges  of  the  slit  meet.  With  a  little  ex- 
perience the  cards  may  be  applied  rapidly,  and  though  involving 
considerable  handwork,  the  testimony  of .  those  who  have  used 
them  for  many  years  shows  that  the  method  is  entirely  practical 
and  is  to  be  preferred  to  doubtful  remedies. 

A  mixture  of  lime  and  carbolic  acid  has  recently  been  used 
by  applying  it  to  the  surface  of  the  soil  around  the  plants, 
so  as  to  form  a  slight  crust,  the  carbolic  acid  acting  pos- 
sibly as  a  repellant.  The  lime  is  slaked  to  a  thin  cream,  and 
diluted  to  3  pints  to  a  gallon  of  water  to  which  is  added  a  table- 
spoonful  of  crude  carbolic  acid.     It  is  applied  liberally  to  the 


320       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


soil  immediately  around  the  plants  with  a  sprinkling  can.  This 
has  proven  quite  effective  for  cabbage  in  New  Jersey,  but  in 
Minnesota  cabbage  so  treated  showed  but  little  benefit,  though 
radishes  were  somewhat  protected.  Kerosene  and  sand,  gas 
tar  and  sand,  tobacco  dust  and  many  other  substances  have  been 
used  to  place  around  the  plant  and  act  as  repellants  or  preven- 
tives, but  all  have  some  objection  or  have  not  been  sufficiently 
tested  to  show  their  effectiveness  and  practicability.  Dr.  J.  B. 
Smith  reports,  however,  that  cauliflower-growers  at  Richfield, 
N.  J.,  have  been  using  gas  tar,  1  part  to  25  parts  of  sand,  for 

several  years  with  good  re- 
sults. The  gas  tar  costs  $1.25 
a  gallon  and  will  treat  1000 
plants.  A  greater  propor- 
tion of  gas  tar  has  proven 
injurious. 

Remedies. — For  the  de- 
struction of  the  maggots, 
both  carbolic  acid  emulsion 
and  hellebore  decoction  have 
been  extensively  used  with 
varying  results,  but  from  the 
evidence  so  far  submitted, 
the  grower  would  hardly 
seem  warranted  in  placing 
much  dependence  upon 
them,  though  where  preven- 
tive measures  have  been  neg- 
lected, they  may  aid  in  reducing  the  number  of  maggots  and  pre- 
vent a  total  loss. 

The  surest  method  of  destroying  the  maggots  on  the  roots  is 
by  the  use  of  carbon  bisulfide.  This  is  entirely  practicable 
on  a  few  plants,  but  has  not  come  into  general  use  on  a  large 
scale,  as  no  satisfactory  tool  for  its  injection  into  the  soil  is  avail- 
able. A  small  hole  should  be  made  with  a  dibble  4  to  6  inches  from 
the  infested  stem,  and  a  teaspoonful  of  carbon  bisulfide  injected  and 
the  hole  tightly  closed  with  earth.  If  made  too  close  to  the  plant 
the  roots  will  be  injured.  The  fumes  kill  the  maggots  by  permeat- 
ing the  soil.  Where  plants  are  badly  infested  injection  on  two 
sides  may  be  necessary. 


Fig.  269. — a,  tarred  felt  card  in  outline 
one-third  size;  h,  tool  for  cutting 
cards,  about  one-sixth  size;  c,  show- 
ing how  tool  is  used,  dotted  line 
indicating  position  of  edge  of  tool. 
(After  Goff.) 


INSECTS  INJURIOUS  TO  CABBAGE,  Etc. 


321 


The  Imported  Cabbage  Worm  * 

Probably  the  worst  pest  of  the  cabbage  and  one  of  the  best- 
known  garden  insects  is  the  common  cabbage  worm,  whose  parent 


^'•d,    J  Btf (i&haftt, 


Fia.  270. — The  cabbage  butterfly  {Pontia  rapce  Linn.):  a,  larva;  b,  chrysalis; 
c,  male  butterfly;  d,  female  butterfly.     (After  C.  M.  Weed.) 

is  the  common  white  butterfly.     It  is  an  old  European  pest  and 

was  imported  near  Quebec,  Canada,  about  1860,  whence  it  spread 

*  Pontia  rupee  Linn.     Family  Pieridoe.   See  F.  H.  Chittenden,  Bulletin  766 , 
U.  S.  Dept.  Agr. 


322       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


to  New  England,  reached  New  York  in  1868,  Cleveland,  Ohio,  by 
1875,  and  the  Gulf  States  by  1880,  and  has  since  spread  to  all  parts 
of  the  country. 

The  butterflies  are  among  the  first  to  emerge  in  early  spring. 
They  are  white,  marked  with  black  near  the  tip  of  the  fore-wings, 
which  expand  nearly  2  inches.  The  female  bears  two  black  spots 
on  each  fore-wing,  while  the  male  has  only  one,  and  both  sexes  have 
a  black  spot  on  the  anterior  margin  of  the  hind-wings. 

Life  History. — The  butterflies  soon  commence  to  lay  their  eggs 
on  whatever  food-plant  is  available.  The  larvae  feed  on  all  of  the 
common  cultivated  crucifers  as  well  as  many  wild  sorts,  so  that  the 
species  is  never  without  food.     The  small  yellowish,  oval  eggs  are 


Fig.  271. — Pteromalus  piiparum,  a  chalcis-fly  which  parasitizes  the  cabbage 
worm  and  many  other  injurious  insects,  male  and  female  greatly  enlarged 
— hair  line  shows  natural  size.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

laid  on  end  on  the  foliage,  and  are  marked  with  prominent  longi- 
tudinal ridges.  They  hatch  in  from  four  to  eight  days.  The  larvae 
grow  very  rapidly,  gorging  themselves  on  the  foliage,  which  they 
skeletonize  in  their  well-known  manner,  and  become  full  grown  in 
from  ten  days  to  two  weeks.  The  mature  cabbage  worm  is  about 
Ij  inches  long,  of  a  velvety  green  color,  very  similar  to  the  foliage, 
with  a  faint  yellow  stripe  down  the  middle  of  the  back  and  a  row 
of  yellow  spots  on  each  side.  The  surface,  when  seen  under  a 
lens,  is  finely  roughened  and  dotted  with  small  black  specks.  The 
chrysalis  is  attached  to  the  foliage  by  a  strand  of  silk  around  the 
thorax  and  is  first  greenish  and  later  light  brown  in  color.  The 
butterflies  emerge  in  from  one  to  two  weeks  in  the  summer,  but 
the  chrysalides  of  the  last  generation  in  fall  hibernate  over  winter 
among  the  old  stalks  and  rubbish  on  the  fields.  Thus  the  whole 
life  cycle  in  summer  requires  from  three  to  five  weeks.     In  New 


INSECTS  INJURIOUS  TO  CABBAGE,  Etc. 


323 


England  there  are  three  generations  a  season  and  there  are  prob- 
ably five  or  six  in  the  extreme  South,  as  the  butterflies  there  remain 
on  the  wing  all  winter. 

Enemies. — Fortunately,  the  parasites  of  the  cabbage  worm  are 
becoming  very  effective  in  checking  its  multiplication,  and  in 
many  sections  of  New  England  where  it  has  existed  the  longest, 
it  rarely  becomes  very  injurious,  so  well  do  the  parasites  control 
it.  Most  of  these  are  importations  from  Europe,  one  of  the 
most  important  being  a  small  wasp-like  Braconid  fly  (Apanteles 
glomeratus  Linn.)  which  was  purposely  imported  from  England 
in  1883.     During  the  autumn  of  1904  Dr.  Chittenden  states  that 


v^,.^^^, 
S^^^" 


Fig.  272. — Apanteles  glomeratus,  a  parasite  of  the  cabbage  worm:  a,  adult 
fly;  h,  cocoon;  c,  flies  escaping  from  cocoons — natural  size,  a,  b,  highlj' 
magnified.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

it  killed  practicafly  every  worm  at  Washington,  D.  C.  The  maggots 
of  these  little  parasites  live  within  the  worms  and  when  full  grown 
come  forth  and  spin  masses  of  small  white  cocoons  on  the  foliage, 
often  attached  to  the  dead  or  dying  worm  (Fig.  272).  Another 
very  important  parasite  is  a  minute  Chalcis-fly  (Pteromalus 
puparum  Linn.),  about  one-sixteenth  of  an  inch  long,  which  was 
probably  unported  with  its  host.  These  often  emerge  in  immense 
numbers,  hundreds  of  them  often  being  secured  from  a  single 
worm.  Wasps  frequently  prey  on  the  caterpillars,  using  them  for 
provisioning  their  nests.  Various  predaceous  bugs  also  attack 
the  worms  as  well  as  numerous  other  internal  parasites. 


CABBAGE 


The 
Imported 

Cabbage 
But-terfly 

is  tKe  parent  of  the 
COMMONjn^ 
CABBAGE  --  "^^ 

terf  lies  lay 


^ai 


The  Cabbag"e 
Looper 
is 
the 
pyoun^ofaMoth 


t}ieire??s  mostly 
on  under  sides  of 
the  cabbage  leaves. 
The  youn?  worms  , 

hatch  from  them  in.       \>>  The  looper  worm  spins  a, 
4  to  8  days,  feed  on  the         cocoon  Inwhichit  changes 
leaves  and  reach  matur-        to  a  pupa  before  trans- 
it/ in  10  to  H  days  Then  forming  to  the  moth. 
'f\  each  attaches  itself  by 
a  thread  around  the  bod/ to  a  leaf , 
stalk, fence  post,cran/  other  fapport,aiid  transforms  to  a 
pupa  called  a  chrysalis-  From  this  the  butterfly  emerges 
in  from  7  to  12  days.  In  northern  States  there  may  be  three 
fenerations  durins  the  season  and  in  southemStates  five 
orsix.  The  last  chrysalides  formed  in  fall  re  main  thus  over 
winter  on  dead  stalks  and  produce  butterflies  the  fol- 
lowing spnn  j. 

SPRAY 

"With  an 

ARSENICAL 

in  soapy  vsrater 


j^,  J  To  make  SOgallons  of  spray  dissolve  41i3.dlauiv 

atbssie     dry  soap  orother  good  soap  in  several  jallons  of  water  by  boil- 
r"i  ins  Add  this  to  encush water  tomake  SOgatlons. Thcnatir 

in  the  aijenicaU  IHlbi  of  powdered  arscrwte  of  leader  J  Ihs. of  puis 
form, or  other  arsenic  als  according  to  directions  on  i>«ckage).Tle 
soapistomahe  the  liquid  adhere  htlter  to  iKe  smooth  leaves. 

To  make  oncgaUonof  spray  use  Vt  oz  of  powde  red  arsenate 
of  lead  .or  loz.  of  paste  form,  and  an  inch  cube  of  soap. 

DUSTING  may  be  substituted  for  spraying. usinglpart of 
powdered  arsenical  wilh4-  parts  of  air-slaKed  lime.  Jn  small  jai* 
dens  the  mixture  rriay  be  shaken  on  the  plants  from  a  cheesecloth 
bay  Apply  thinly  while  the  dew  is  on  the  leaves. 
lk.ir>T  CDO  AVCT»  Since  therabbageheadgrows  frominsidetheplant 

N*-' '  ^  KK  AY  tU  there  is  no  danger  trompoisoning.H  outer  leaves  are  re- 

moved before  cooking  spraying  isBafe  to  within  three 
of  season  from  severe       weeks  of  harvest  H  spraying  is  begun  early  in  the  sea- 
.JVote  u-r.devehped  head  .<;on  the  re  will  belittle  damaje  from  late  broods  ofwormi 


Fig.  273.— Bureau 
cabbage  worms. 


of    Entomology  (U.  S.  Dept.    of   Agr.)    chart  showing 


324 


INSECTS  INJURIOUS  TO  CABBAGE,  Etc. 


325 


Control. — As  the  chrysalids  pass  the  winter  on  the  old  stumps, 
foliage,  and  rubbish  on  the  field,  it  is  evident  that  they  should  be 
destroj'^ed  and  the  field  plowed  as  soon  after  the  crop  is  removed 
as  possible.  A  few  stalks  may  well  be  left  standing  here  and 
there  and  be  kept  well  poisoned,  so  as  to  act  as  traps  to  destroy 
worms  from  eggs  laid  by  late  female 

The  most  effective  means  of  control  is  spraying  or  dusting 
with  Paris  green  or  arsenate  of  lead.  The  former  is  used  ^  pound 
to  the  barrel  and  the  latter  2  to  3  pounds  per  barrel  of  water. 
As  the  foliage  of  cabbage  is  extremely  smooth  it  will  be  advisable 
to  add  2  or  3  pounds  of  resin  soap  or  "  sticker  "  to  render  the 
material  more  adhesive.  The  arsenicals  should  be  applied  as 
soon  as  the  plants  are  set,  and  they  should  be  kept  well  covered 
until  the  heads  are  half  formed.     If  this  is  done,   the  young  larvae 


Fig.  274. — The  southern  cabbage  butterfly;  a,  male;  b,  female.     (After  Riley.) 

will  be  destroyed  before  they  burrow  into  the  heads,  and  there 
will  be  but  little  damage  after  the  spraying  is  stopped.  Although 
there  is  some  prejudice  against  poisoning  cabbage,  it  is  entirely 
unfounded,  for  it  has  been  shown  that  a  person  would  neeki  to  eat 
twenty-eight  cabbages  at  once,  if  dusted  in  the  ordinary  manner, 
to  secure  poisonous  effects.  It  is  obvious  that  plants  should  not 
have  large  quantities  of  dust  placed  on  them  after  they  commence 
to  head,  and  such  applications  are  entirely  unnecessary. 

Various  contact  insecticides  may  be  used  against  the  worms 
on  a  few  plants,  but  are  not  practicable  for  large  acreages.  Thus 
water  heated  to  150°  F.,  will  kill  all  the  worms  which  it  hits. 
Kerosene  emulsion  will  kill  the  larvae,  but  must  hit  them,  and 
may  leave  an  odor  on  the  plant.  Pyrethrum  or  buhach  has  been 
used  effectively,  applying  it  either  dry  or  diluted  with  flour, 
or  sprayed  as  a  decoction  at  the  rate  of  1  ounce  to  a  gallon  of 
water.     Dilute  tobacco  extract  has  also  proven  effective,   but 


326       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Fig.  275. —  The  southern  cabbage  butterfly: 
a,  larva;  h,  pupa.     (After  Riley.) 


all  of  these  substances  have  the  disadvantage  that  they  must 
be  brought  into  actual  contact  with  the  worms  to  kill  them. 

The  Southern  Cabbage  Butterfly  * 

Before  the  invasion  of  the  imported  cabbage  worm  this  species 
was  the  cause  of  considerable  injury  from  the  Middle  States 

southward,  but  it  has 
now  been  largely  replaced 
and  overshadowed  in  im- 
portance by  the  imported 
species.  The  male  but- 
terfly is  very  similar  in 
marking  to  the  female  of 
P.  rapoe,  and  would  not 
be  distinguished  on  the 
wing.  The  female  is 
more  heavily  marked  with 
black,  as  shown  in  the  figure.  The  caterpillar  is  a  greenish-blue 
color  with  four  longitudinal,  yellow  stripes,  and  covered  with  black 
dots.  The  habits  are  very  similar  to  those  of  the  imported  cab- 
bage worm,  and  the  same  methods  of  control  should  be  used. 

The  Potherb  Butterfly  f 

This  species  is  more  common  in  the  North  and  East   and   is 
distinguished  from  its  near  rela- 
tives by  the  wings  being  uniform 
white  without  spots.      The  larva 
are  very  similar  to  those  of  the 
imported   species   and  the  habits 
are  very  similar.     Like  the  south- 
ern species,  though  formerly  very 
common  and  often  injurious,  this 
species    is    now    rarely    common 
enough  to  do  much  injury  and  Fig.    276.— The  potherb  butterfly 
feeds  mostly  on  wild  plants.     The      and  caterpillar.     (After  Harris.) 
same  remedies  as  for  the  imported  species  should  be  used. 

*  Pontia  protodice  Boisd.     Family  PieridcB. 
t  Pontia  napi  Linn.     Family  Pieridce. 


INSECTS  INJURIOUS  TO  CABBAGE,  Etc. 


327 


The  Cabbage  Looper 


Next  to  the  imported  cabbage  worm  the  looper  is  probably 
the  most  serious  pest  of  cabbage  and  closely  resembles  it  in  the 
way  it  strips  the  foliage.f  The  name  "  looper  "  is  derived  from 
its  "  looping  "  habit  of  walking  like  a  measuring  worm,  due  to  the 
absence  of  legs  on  the  third  and  fourth  abdominal  segments.  The 
larvae  are  pale  to  dark  green  in  color,  marked  with  several 
longitudinal  white  lines,  as  shown  in  Fig.  277,  which  become 
obscure  as  they  become  full  grown,  so  that  they  might  be  easily 
mistaken  for  the  com- 
mon cabbage  worms 
were  it  not  for  the 
looping  gait.  The 
species  occurs 
throughout  the  ter- 
ritory east  of  the 
Rockies,  but  is  much 
more  commonly  in- 
jurious in  the  Middle 
and  Southern  States. 
Although  cabbage  and 
cauliflower  are  the  fa- 
vorite food  plants,  it 
attacks  all  of  the  cru- 
ciferous crops,  is  fre- 
quently injurious  to 
lettuce,  peas,  celery 
and  beets,  and  has 
been  found  upon  quite 
a  list  of  cultivated 
crops  and  various 
weeds. 

Life  Histonj. — The  life  history  has  not  been  carefully  observed, 
but  it  seems  probable  that  the  winter  is  passed  in  the  pupa  stage 
in  the  old  leaves,  stumps  and  rubbish  of  the  cabbage  field.     Sirrine 

*  Autographa  brassicoe  Riley.     Family  Nociuidoe.    See  F.  H.  Chittenden, 
Bulletin  33,  n.  s.,  Div.  Ent.,  U.  S   Dept.  Agr.;  F.  A    Sirrine   Bulletin  144, 
N.  Y.  Agr.  Exp.  Sta. 
t  See  also  page  324 


Fig.  277— The  cabbage  looper  (Autographa  bras- 
sicoe Riley):  a,  male  moth;  b,  egg  from  above 
and  from  side;  c,  full  grown  larva  in  natural 
position  feeding;  d,  pupa  in  cocoon — a,  c,  d, 
one-third  larger  than  natural  size,  b,  more 
enlarged.  (After  Howard  and  Chittenden, 
U.  S.  Dept.  Agr.) 


328       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


states  that  the  hfe  history  is  similar  to  that  of  the  imported 
cabbage  worm,  and  it  seems  probable  that  there  are  three  genera- 
tions a  year  in  the  Middle  States,  and  possibly  more  farther 
South.  Injury  to  cabbage  seems  to  be  worse  in  late  summer. 
When  full  grown  the  larva  spins  a  very  thin,  transparent,  white 
cocoon,  attached  to  the  leaf  upon  which  it  has  been  feeding  and 
in  it  transforms  to  the  light-brown  pupa.  The  pupal  stage  varies 
from  a  week  in  midsummer  to  three  weeks  in  October,  and  the 
pupae  of  the  last  brood  hibernate  over  winter. 

The  moth  has  a  wing  expanse  of  about  Ij  inches,  and  the  fore- 
wings  are  grayish-brown  mot- 
tled with  gray,  whitish,  and 
blackish,  as  shown  in  Figs 
277,  278.  Just  inside  of  the 
centre  of  the  fore-wings  is  a 
characteristic  white  spot.  The 
hind-wings  are  paler  brown, 
with  the  outer  border  darker, 
and  the  margins  of  both 
wings  are  strongly  scalloped. 

Control. — The  same  general 
methods  as  advised  for  the  im- 
ported cabbage  worm  will 
effect  the  control  of  this  spe- 
cies. Sirrine  states  that  dust- 
ing the  pla.ts  with  Paris  green 
has  not  proved  satisfactory, 
but  found  the  use  of  Paris 
green  with  the  resin  soap  stick- 
er to  be  very  effective.  Arsen- 
ate of  lead  is  more  adhesive 
and  is  therefore  superior  for 
cabbage  but  will  be  improved  by  the  addition  of  the  "sticker." 


^^^1 

^m 

1 

^^E 

■ 

^^^^^^^^Bj 

^H 

^^^^^1 

Ir-^   -. 

^^^^H 

Ik^  "^^ 

j-fM 

1          1 

Ih 

^^H 

hi 

1 

1 

Fig.  278. — The  cabbage  looper  moth 
at  rest  from  side  and  from  above  — 
natural  size. 


The  Diamond-back  Moth  * 

The  larvse  of  the  imported   diamond-back   moth  or  cabbage 
plutella  are  commonly  found  on  cabbage  wherever  it  is  grown 

*  Plutella  maculipennis  Curtis.     Family  Tineidoe. 


INSECTS  INJURIOUS  TO  CABBAGE,  Etc. 


329 


and  as  a  rule  do  but  little  injury,  though  occasionally  they  be- 
come troublesome. 

"  The  larvae  when  full  grown  measures  three-tenths  inch  in 
length,  tapers  a  little  to  the  extremities,  and  is  of  a  pale  green 
color.  It  is  active  and  irritable,  in  this  respect  being  very 
different  from  any  of  the  larger  larvsB  described."  The  wings 
of  the  parent  moth  "  are  kept  folded  against  the  sides  of  the  body, 
are  a  little  turned  up  at  the  tips,  and  are  provided  with  a  long 
fringe.  The  color  above  on  the  head,  thorax,  and  upper  part 
of  the  closed  wings  is  a  light  clay-yellow.  That  part  of  the 
wings  that  is  lowest  when  they  are  folded  is  bronze  brown,  this 
color  terminating  abruptly  where  it  meets  the  clay-yellow  of 
the  back  by  a  well-defined  sinuous  margin.  The  length  from 
the  front  of  the  head  to 
the  tip  of  the  folded 
wings  is  about  one- 
fourth  inch."* 

"  The  eggs  are  whit- 
ish, very  minute,  and 
are  attached  to  the 
leaves,  though  some- 
times when  very  abun- 
dant they  are,  it  is  said, 
placed  on  the  sides  of 
crates  holding  cab- 
bage." The  full-grown 
larvae  pupate  in  small 
cocoons  composed  of  a  delicate  lace-work  of  silken  threads  through 
which  the  whitish,  often  brown-striped,  pupa  may  be  seen.  In 
winter  the  cocoons  containing  pupae  are  found  on  old  cabbage 
stalks  in  the  field  or  on  stored  cabbage.  Two  or  three  genera- 
tions a  year  occur  in  the  more  northern  states  and  four  or  five 
generations  farther  south,  while  in  the  extreme  South  it  may  be 
found  active  practically  throughout  the  year.  The  species  has  a 
world-wide  distribution. 

"  During  very  dry  weather  these  little  insects  become  exceed- 
ingly common,  and  riddle  the  cabbage  leaves  with  small  holes. 
Wet  weather,  on  the  other  hand,  has  long  been  known  to  be 

*  H.  Garman,  Bulletin  114,  Ky.  Agr.  Exp.  Sta.,  p.  29. 


Fig.  27P. — The  cabbage  plutella  or  diamond- 
back  moth  {Plutella  macidipennis  Curtis) :  a, 
larva;  b,  segment  of  same  greatly  enlarged;  d, 
pupa;  e,  pupa  in  cocoon;  /,  adult  moth;  g, 
wings  of  dark  varietv;  h,  moth  with  wings 
folded.     (After  Riley^  U.  S.  Dept.  Agr.) 


330        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


unfavorable  to  them,"  and  drenching  the  plants  with  water  has 
been  recommended  as  one  of  the  best  means  of  control.  The 
same  remedies  applied  for  the  other  cabbage  worms  will  readily 
control  this  little  pest. 


Fig.  280. — The  harlequin  cabbage  bug  (Murgantia  histrionica  Hahn.) :  a, 
eggs — enlarged;  h,  nymphs,  more  enlarged;  d,  adults  seen  from  above 
and  below — enlarged;  e,  head  and  beak  of  same;  /,  parasite  of  eggs — 
enlarged;  bugs  and  eggs  (a)  on  leaf,  natural  size.     (After  W.  G.  Johnson.) 

The  Harlequin  Cabbage-bug  * 

Southern    truckers  have   been   familiar   with   the   harlequin 

cabbage-bug,    "  calico-back,"   "  terrapin-bug,"   or  "  fire-bug,"  as 

*  Mtirgantia  histrionica  Hahn.  Family  Pentaiomidoe.  See  F.  H.  Chitten- 
den, Farmers'  Bulletin  1061,  U.  S.  Dept.  Agr.;  R.  I.  Smith,  Journal  Economic 
Entomology,  Vol.  II,  p.  108,  and  F.  B.  Paddock,  Bulletin  179,  Texas  Agr. 
Expt.  Station. 


INSECTS  INJURIOUS  TO  CABBAGE,  Etc. 


331 


it  is  variously  called,  for  the  past  generation.  A  native  of 
Mexico  and  Central  America,  it  migrated  into  Texas  about  1864 
and  then  spread  eastward  along  the  Gulf  Coast,  and  northward 
until  it  reached  Maryland  and  Virginia,  about  1880,  New 
Jersey  in  the  early  90's,  and  up  the  Mississippi  Valley  to  southern 
Ohio  and  Indiana  by  1890.  On  the  Pacific  Coast  it  is  found  in 
southern  California  and  Nevada.  Although  it  spread  to  Long 
Island,  N.  Y.,  southern  Pennsylvania,  and  northern  Ohio,  and 
Indiana,  its  advance  was  checked  by  the  cold  winters  of  the  late 


Fig.  '2S;1. — lirld  of  cabbage  in  Delaware  ruined  by  the  harlequin  bug. 

90's  and  it  will  probably  never  become  very  injurious  north  of 
the  Potomac  and  Ohio  rivers. 

The  appearance  of  the  gayly  colored  bugs,  shining  black  or 
deep  blue,  marked  with  brilliant  red  or  orange,  as  shown  in 
Fig.  280,  is  so  distinctive  that  they  are  readily  recognized,  and 
gives  them  the  name  of  harlequin-bug  or  calico-back.  They 
are  about  one-half  inch  long,  flattened,  and  the  general  shape 
and  markings  have  given  them  the  local  name  of  "  terrapin 
bug."  The  bugs  suck  the  sap  from  the  leaves  of  cabbage  and  other 
crucifers,  the  plants  wilting  and  dying,  and  turning  black  as  if 


332       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

they  had  been  swept  by  fire;  hence  the  name  "  fire-bug."  A 
half-dozen  of  the  adult  bugs  will  destroy  a  small  plant  in  a  day 
or  two,  and  as  they  frequently  appear  in  enormous  numbers  and 
as  they  multiply  rapidly,  unless  they  are  fought  vigorously  they 
will  soon  destroy  a  large  patch  of  cabbage. 

Life  History. — The  adults  hibernate  over  winter  in  old  cabbage 
stumps  and  under  the  leaves  and  other  rubbish  left  on  the  field, 
and  emerge  early  the  next  spring.  In  South  Texas  they  may 
be  found  at  work  nearly  all  winter,  being  common  in  February 
and  March ;  in  North  Carolina  they  appear  about  April  1st,  and  in 
Maryland  about  May  1st.  The  eggs  of  the  first  generation  are 
deposited  mostly  on  kale,  wild  mustard  or  other  wild  cruciferae, 
each  female  laying  about  100.  They  are  placed  in  a  double 
row  of  about  a  dozen  and  are  white,  marked  with  two  black  bands 
and  a  small  spot,  which  makes  them  look  like  small  white  barrels 
with  black  hoops.  The  eggs  of  the  spring  generation  hatch  in 
about  ten  days,  and  the  nymphs  feed  upon  the  cabbage  for  from 
six  to  nine  weeks  before  becoming  full  grown  in  North  Carolina 
and  the  District  of  Columbia,  while  in  the  Gulf  States  the  eggs 
hatch  in  four  to  eight  days  and  the  nymphs  become  full  grown 
in  three  or  four  weeks,  the  development  of  these  stages  being 
determined  by  the  temperature.  The  nymphs  are  much  like 
the  adults  in  coloration,  though  differently  marked  and  lacking 
wings.  They  molt  five  times,  some  of  the  different  stages  being 
shown  in  the  figure.  From  North  Carolina  northward  there 
seem  to  be  but  three  generations  of  the  insect.  The  summer 
generation  develops  more  rapidly,  the  eggs  hatching  in  four  or 
five  days,  but  the  fall  generation  requires  about  the  same  time  as 
in  spring.  In  midsummer  the  whole  life  cycle  may  be  passed  in 
about  two  weeks  in  the  Gulf  States,  according  to  various  author- 
ities, so  that  there  may  be  a  half  dozen  generations,  though  the 
exact  life  history  does  not  seem  to  have  been  observed  there. 

Control. — This  is  an  exceedingly  difficult  pest  to  combat  after 
it  has  become  numerous  in  the  cabbage  patch,  so  that  every  effort 
should  be  made  to  prevent  its  appearance.  As  it  hibernates  under 
old  stalks  and  leaves  it  is  obvious  that  they  should  be  cleaned  up 
and  the  field  plowed  as  soon  as  the  crop  is  harvested.  By  leaving 
a  few  piles  of  stalks,  leaves  and  rubbish,  the  bugs  might  be  concen- 
trated and  then  destroyed. 


INSECTS  INJURIOUS  TO  CABBAGE,  Etc.  333 

The  most  successful  method  of  control  yet  devised  is  the  use 
of  a  trap-crop,  to  which  the  bugs  are  lured  as  they  emerge  from 
hibernation  and  on  which  they  may  be  destroyed  before  they 
attack  the  cabbage.  Kale  planted  in  the  fall  or  mustard  planted 
early  in  the  spring  serves  well  for  a  catch  crop,  and  should  be 
planted  in  rows  through  the  intended  cabbage-field.  The  bugs 
seem  to  prefer  the  kale  to  the  young  cabbage,  and  while  concen- 
trated upon  it  they  should  be  killed  by  spraying  them  with  pure 
kerosene.  The  trap-crop  may  well  be  planted  at  different  dates, 
so  that  after  one  row  has  been  destroyed  by  spraying,  another  will 
invite  the  remaining  bugs.  The  nymphs  may  be  destroyed  by 
spraying  them  with  15  per  cent  kerosene  emulsion  or  whale-oil  soap, 
one-half  pound  per  gallon.  Whale-oil  soap  used  at  the  rate  of  1  to 
2  pounds  to  the  gallon  will  kill  most  of  the  adult  bugs  hit  by 
it  without  injury  to  the  cabbage,  but  dependence  should  not  be 
placed  upon  control  by  spraying,  as  its  practicability  on  a  large 
scale  is  yet  to  be  demonstrated. 

The  Cabbage-aphis  * 

Wherever  cabbage  is  grown  the  common  "  cabbage-louse  " 
occasionally  becomes  abundant  enough  to  do  serious  damage, 
often  destroying  young  plants,  which  become  covered  with  the 
disgusting  masses  of  grayish  aphids.  They  are  found  commonly 
in  almost  every  cabbage-patch,  but  usually  their  natural  enemies 
are  so  effective  as  to  prevent  their  increase;  otherwise  they  would 
be  one  of  the  most  serious  pests  of  cruciferous  crops.  They  may 
be  found  on  all  of  the  cultivated  and  wild  cruciferse,  but  cabbages 
and  turnips  are  injured  worst,  serious  damage  often  being  done  to 
turnips  in  the  South. 

*'  The  wingless  viviparous  female  has  a  rather  long  oval  body, 
covered  with  a  whitish  mealy  coat.  When  this  coat  has  been 
removed  .  .  .  the  body  is  seen  to  be  a  grayish-green  color,  with 
eight  black  spots  down  either  side  of  the  back,  increasing  in  size 
toward  the  posterior  end.  The  antennae  are  green  with  black  tips, 
and  are  shorter  than  the  body,  and  the  eyes,  legs  and  tail  are 

*  Aphis  brassicoe  Linn.  Family  Aphididoe.  See  C.  V.  Riley,  Report  of 
U.  S.  Commissioner  of  Agriculture,  1884,  p.  317.  C.  M.  Weed,  "Insect 
Life,"  Vol.  Ill,  p.  289.  G.  W.  Herrick,  Bulletin  300,  Cornell  Univ.  Expt. 
Station.  F.  H.  Chittenden  and  C.  H.  Popenoe,  Bulletin  2,  Va.  Truck  Exp. 
Sta.,  p.  22. 


334        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


black.  The  young  when  first  hatched  are  oval,  shining,  bright 
yellow  in  color,  and  lack  the  mealy  coat.  The  winged  viviparous 
female  is  yellowish-green,  with  the  eyes,  neck  and  thoracic  lobes 
black,  and  the  antennae  and  nectaries  dark  brown.  The  legs  are 
dusky  brown  and  hairy;  the  tail  is  dark  green  or  brown  and  also 
hairy;  the  wings  are  rather  short,  with  stout  coarse  veins  and  dark 
stigma."     (Riley). 

Life  History. — Though  the  cabbage-aphis  is  an  old  European 
species  and  was  observed  in  this  country  as  early  as  the  latter  part 
of  the  eighteenth  century,  its  life  history  has  only  recently  been 
carefully  worked  out  by  Professor  G.  W.  Herrick  and  Mr.  J.  W. 
Hungate  of  Cornell  University  (I.e.),  from  whose  account  the  fol- 
lowing is  taken : 

The  oviparous  females  appear  in  the  fall  and  are  fertilized  by 

the  males,  and  deposit 
their  eggs  in  large  num- 
bers on  the  leaves  of  the 
cabbage,  during  October 
and  the  first  days  of 
November,  in  central 
New  York.  The  eggs 
are  laid  on  rape,  turnip, 
brussels  sprouts  and 
kohl-rabi  but  are  most 
abundant  on  cabbage, 
particularly  in  the  crevices  and  depressions  of  the  under  surfaces  of 
the  leaves.  On  leaves  taken  at  random  from  a  badly  infested  patch, 
from  177  to  293  eggs  were  found  on  a  leaf.  Two  to  three  eggs  are 
laid  by  each  oviparous  female.  When  first  laid  the  eggs  are  a 
yellowish-green,  but  soon  turn  a  shining  black.  From  eggs  taken 
at  random  and  left  under  normal  outdoor  conditions,  76  per  cent 
hatched  the  next  spring,  while  all  eggs  hatched  which  were  laid  by 
females  known  to  have  been  fertilized.  Eggs  hatched  about 
April  1,  1910,  in  central  New  York,  the  season  being  an  early  one. 
From  the  stem  mothers  which  hatched  from  these  eggs,  twenty- 
one  generations  of  wingless  females  were  reared  up  to  December  3, 
1910,  the  average  length  of  a  generation  being  about  twelve  days. 
During  the  summer  generations  of  winged  females  are  produced, 
especially  on  crowded  plants,  and  these  serve  to  spread  the  pest  to 


Fig.  282. — The  cabbage-aphis  (Aphis  brassicoe 
Linn.) :  a, winged  form;  b,  wingless  viviparous 
female — greatly  enlarged.     (After  Curtis.) 


INSECTS  INJURIOUS  TO  CABBAGE,  Etc.  335 

unafiected  plants.  The  wingless  females  become  full  grown  in 
about  thirteen  days  during  the  summer  and  live  for  about  forty-six 
days,  during  which  time  they  will  give  birth  to  an  average  of  forty- 
one  young,  producing  as  high  as  six  young  in  a  day.  The  winged 
forms  are  much  shorter  lived,  living  only  about  ten  days  and  giving 
birth  to  but  from  seven  to  thirteen  young. 

There  is  no  question  that  in  the  Southern  States  the  viviparous 
females  may  continue  to  reproduce  all  winter,  and  it  is  quite  prob- 
able that  some  of  them  survive  in  pits  and  cellars  in  the  North, 
where  eggs  also  probably  occur.  Thus  Sirrine*  states  that  it  "is 
certain  that  this  aphid  can  survive  the  winter  on  cabbage  stored 
in  cellars  or  pits,  also  that  cabbage  stored  in  pits  for  seed  purposes 
furnishes  the  supply  of  aphids  for  infesting  the  seed  stalks  in  early 
spring."  This  being  the  case  it  should  be  an  easy  matter  to  de- 
stroy the  aphids  by  fumigation  before  removing  them  from  the  pits. 

Control. — From  the  habits  outlined  it  is  evident  that,  as  for 
other  cabbage  pests,  the  refuse  of  the  crop  should  be  cleared  up  and 
destroyed  in  the  fall.  Any  of  the  standard  contact  insecticides, 
such  as  kerosene  emulsion,  1  part  stock  solution  to  15  parts  of 
water,  whale-oil  soap,  1  pound  to  6  gallons,  or  "  Black-leaf  40," 
1  part  to  800  of  water,  will  destroy  the  aphids,  but  the  spray- 
ing must  be  thorough,  as  the  waxy  coating  serves  to  protect 
them.  According  to  Professor  Franklin  Sherman,  any  good 
laundry  soap  used  at  the  rate  of  1  pound  dissolved  in  3  gallons  of 
water,  will  destroy  the  aphids.  Where  water  under  pressure  is 
available  in  a  small  garden,  the  aphids  may  be  held  in  check  by 
washing  them  from  the  plants  with  a  strong  stream  from  a  garden 
hose.  Plants  infested  in  the  seed-bed  may  be  freed  from  the 
aphis  by  dipping  in  whale-oil  soap  solution,  1  part  to  8  of  water. 

Fortunately  for  the  grower,  the  cabbage-aphis  is  usually  held 
in  check  by  numerous  parasitic  enemies,  principally  little  wasp- 
like flies  of  the  family  Braconidce,  and  by  several  species  of  lady- 
bird-beetles and  syrphus-fly  larvae,  which  will  often  destroy  a 
colony  within  a  few  days. 

The  Spinach-aphis  or  Green  Peach-aphis  f 

Another  species  of  aphis  often  becomes  destructive  to  cabbage, 
spinach,  celery  and  lettuce,  as  well  as  various  greenhouse  crops 

*,F.  A.  Sirrine,  Bulletin  83,  N.  Y.  Agr.  Exp.  Sta.,  p.  675. 
t  Myziis  persicoe  Sulz. 


336       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

In  the  fall  it  migrates  to  peach,  and  is  also  known  as  the  green 
peach-aphis,  as  which  it  is  discussed  on  page  587 

The  Turnip  Louse  * 

The  turnip  louse,  also  called  the  false  cabbage  aphis  has  recently 
been  recognized  as  a  separate  pest  of  crops  of  this  group.  It  is 
rather  southern  in  its  damage  but  extends  over  a  large  part  of 


Fig.  283. — The  spinach-aphis  (Myzus  persicce  Sulz.):  which  often  becomes 
a  cabbage  pest:  a,  winged  adult;  b,  young  nymph;  c,  older  nymph;  d, 
last  stage  of  nymph — all  greatly  enlarged.  (After  Chittenden,  U.  S. 
Dept.  Agr.) 

the  country.     Mr.  Paddock's  excellent  summary  of  the  insect 
according  to  his  observations  in  Texas,  is  given  here  verbatim : 

"  A  new  species  of  plant  louse,  commonly  called  the  turnip 
louse,  and  not  the  cabbage  louse,  as  was  formerly  supposed,  does 
the  damage  to  the  fall  turnips  and  winter  truck.  This  damage  is 
general  over  the  entire  State  of  Texas.     Not  only  do  the  truck 

*  Aphis  psevdobrassicce  Davis.  See  J.  J.  Davis,  Bulletin  185,  Purdue  Univ. 
Expt.  Station;  and  F.  B  Paddock,  Bulletin  180,  Texas  Agr.  Expt.  Station. 


INSECTS  INJURIOUS  TO  CABBAGE,  Etc.  837 

regions  suffer,  but  every  home  garden  is  damaged  by  the  turnip 
louse. 

The  food  plants  of  the  turnip  louse  are  turnips,  cabbage, 
mustard,  cauliflower,  kale,  rutabaga  and  rape. 

The  normal  form  of  reproduction  of  the  turnip  louse  in  Texas 
is  asexual  throughout  the  year.  Observations  have  been  made 
upon  this  louse  in  Texas  from  Brownsville,  on  the  26th  parallel, 
to  Wichita  Falls,  on  the  34th  parallel.  True  hibernation  does  not 
take  place  in  Texas,  even  at  the  northernmost  point  of  occurrence 
the  lice  reproduce  some  during  the  winter.  The  summer  is  the 
critical  period  in  the  life  history  of  the  turnip  louse,  as  it  is  forced 
to  sheltered  locations  and  none  of  the 
cultivated  host  plants  are  grown  at 
that  time  of  the  year.  Thirty-five  gen- 
erations of  the  lice  were  reared  in  pot 
cages  in  one  year. 

Two  other  species  of  plant  life  are 
often  found  closely  associated  with  the 
turnip  louse.  These  are  the  ''garden 
aphis  "   and  the  cabbage  louse. 

The  natural  factors,  of  control  of  the 
turnip  louse  are  widespread  over  the 
State.     Two  species  of  parasites,  Dia- 

erelus  rapae  Curt.,  and  LysivMA^^  ^""..^^'^^lip^Zft^^. 
testaceipes  Cress.,  have  been  commonly  (After  Paddock.) 
found,  the  former  at  College  Station  and  the  latter  in  other  sections. 
Three  species  of  lady  beetles  have  been  observed  to  feed  freely 
on  the  turnip  louse.  These  are  Hippodamia  convergens  Guer., 
Megilla  maculata  DeG.,  and  Coccinella  munda  Say.  Syrphid 
flies  and  lace-wing  flies  are  usually  found  in  limited  numbers 
where  the  turnip  lice  are  abundant.  A  fungous  disease  was  very 
destructive  to  the  turnip  louse  during  the  season  of  1914  at  College 
Station. 

For  the  artificial  control  of  the  turnip  louse,  spraying  is  the  most 
satisfactory  method.  Of  the  materials  which  can  be  used  for  spray- 
ing, laundry  soap  solution  gives  as  satisfactory  results  as  any  and  is 
easily  obtainable.  The  secret  of  success  in  the  control  of  the  turnip 
louse  is  the  use  of  the  45°  elbow  and  an  "  angle  "  type  spray  nozzle. 


338       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

By  the  use  of  these  it  is  possible  to  direct  the  spray  on  the  under 
sides  of  the  leaves,  where  the  lice  feed. 

The  preventive  measures  against  the  turnip  louse  are  rotation, 
proper  planting  time,  trap  crops,  clean  culture,  and  the  destruction 
of  the  first  colonies." 

Flea-beetles  * 

A  considerable  number  of  small  flea-beetles  attack  cabbage  and 
other  cruciferous  crops,  and  although  as  a  rule  only  troublesome, 
they  appear  periodically  in  enormous  numbers  and  do  serious 
injury.  They  are  mostly  small  species  (there  being  seven  species 
of  the  genus  Phyllotreta  alone)  not  over  an  eighth  of  an  inch  long. 
One  of  the  most  common  throughout  the  country  is  the  striped 
turnip  flea-beetle.f  It  is  polished  black  with  each  wing-cover 
marked  with  a  broad,  wavy  band  of  pale  yellow.  The  microscopic 
white  eggs  are  laid  in  a  little  excavation  of  the  root  near  the  crown 
of  the  plant.  The  larvae  mine  into  the  roots  and  have  been 
reported  to  do  considerable  injury  to  them,  but  it  seems  probable 
that  most  of  them  live  upon  the  roots  of  cruciferous  weeds.  The 
full  grown  larva  (Fig.  285a),  is  about  three-eighths  inch  long, 
quite  slender  and  tapering,  yellowish  white,  with  brown  head  and 
anal  plate,  and  with  marks  on  the  thorax  and  transverse  rows  of 
minute  hair-bearing  tubercles  as  shown  in  the  figure.  The  West- 
ern cabbage  flea-beetle  J  is  the  more  common  from  the  Dakotas 
southward  to  Mexico  and  westward  to  southern  California.  It  is  a 
uniform  deep  olive-green,  with  the  surface  irregularly  punctate, 
and  7-100  inch  long.  Another  species  almost  indistinguishable  from 
the  first  species  above,  is  the  wavy-striped  flea-beetle, §  whose  larvae 
mine  in  the  leaves  of  wild  pepper  grass  {Lepidium  virginicum), 
and  is  most  abundant  in  the  Middle  and  Southern  States.  The 
life  history  has  been  fully  described  by  Dr.  Riley  (I.e.). 

Control. — Where  the  plants  are  sprayed  for  the  cabbage  worms 

with  Paris  green  or  arsenate  of  lead,  there  will  probably  be  little 

trouble  with  flea-beetles.     Otherwise,  spray  with  arsenate  of  lead, 

3  to  5  pounds  per  barrel,  or  Paris  green  one-third  to  one-half 

pound,  adding  the  resin  soap  or  "  sticker,"  so  as  to  give  the 

*  Family  Chrysomelidop.     Refer  to  pages  266,  303,  for  other  flea-beetles* 
See  C.  V.  Riley,  Report  U.  S.  Commissioner  Agr.,  for  1884,  pp.  301-308. 
t  Phyllotreta  vittata  Fab. 
X  Phijllotreta  pusilla  Horn. 
§  Phyllotreta  sinuata  Steph.     (zimmermani  Crotch.) 


INSECTS  INJURIOUS  TO  CABBAGE,  Etc. 


339 


foliage  a  good  thick  coating,  for  the  spray  probably  acts  fully 
as  much  as  a  repellant  as  a  remedy.  Where  injury  is  antici- 
pated it  will  be  well  to  dip  the  plants  in  arsenate  of  lead  1  pound 
to  10  gallons  of  water  when  planting  them.  By  thoroughly  dust- 
ing the  plants  with  lime,  land  plaster,  strong  tobacco  dust,  dilute 
pyrethrum,  or  any  of  the  dusts  commonly  used  for  such  insects, 


Fig.  285. — The  striped  turnip  flea-  Fig.  286. — The  western  cabbage  flea- 
beetle  {Phyllotreta  vittata  Pah.):  beetle — much  enlarged.     (After  Riley, 
a,  larva;  b,  adult — greatly  en-  U.  S.  Dept.  Agr.) 
larged.      (After  Riley,   U.   S. 
Dept.  Agr.) 

applying  the  dust  in  the  early  morning  while  the  dew  is  on  the 
plants,  they  may  be  protected  from  attack  as  long  as  they  are 
kept  thoroughly  covered.  It  is  evident  that  the  weeds  upon 
which  these  pests  develop  in  the  larval  stage  should  be  destroyed. 
Where  plants  are  attacked  in  the  seed-bed,  screening  as  advised 
for  the  root-maggot  will  prevent  injury.  Cloth  with  from  20  to  30 
threads  to  the  inch  has  proven  most  satisfactory  for  the  screens, 
which  should  be  applied  early  and  be  made  perfectly  tight. 


CHAPTER  XVIII 


INSECTS  INJURIOUS  TO   MELONS,  CUCUMBERS,  SQUASH,  ETC.* 
The  StripOd  Cucumber-beetle  f 

Just  as  the  httle  cucumber  and  melon  plants  appear  above  the 
soil  they  are  attacked  by  hordes  of  hungry  black-and-yellow-striped 

beetles,  which  feed 
ravenously  upon 
the  succulent  seed- 
leaves,  often  killing 
them  entirely  sothat 
reseeding  is  neces- 
sary. This  little 
striped  beetle,  often 
known  as  the 
"striped-bug  "or 
"melon-bug,"  is 
well  known  to  all 
growers  of  cucurbs 

Fig.  287.— The  striped  cucumber  -beetle  (DiabroHca  east  of  the  Rocky 
vittata  Fab.):  a,  beetle;  b,  larva;  c,  pupa;  d,  egg;  e,  Mountains  and 
sculpture  of  egg — a,  b,  c,  much  enlarged,  d,    more  ' 

enlarged;    e,highly  magnified.      (After  Chittenden,  also      OCCUrs    in 
S.  Dept.  Agr.)  Washington. 

The  beetle  is  about  two-fifths  inch  long  and  half  as  wide,  of  a 
bright  yellow  color  with  a  black  head  and  three  black  stripes  on 
the  wing-covers. 

Life  History. — The  beetles  hibernate  over  winter  in  the  ground 
where  they  have  been  feeding  the  previous  fall,  or  along  the  edge  of 
woodlands,  or  wherever  suitable  shelter  is  obtained,  and  emerge 
in  the  spring  two  or  three  weeks  before  cucurbs  are  planted.     At 

*  See  A.  L.  Quaintance,  Bulletin  45,  Geo.  Agr.  Exp.  Sta.;  J.  B.  Smith, 
Bulletin  94,  N.  J.  Agr.  Exp.  Sta.;  R.  I.  Smith,  Bulletins  205  and  214,  No. 
Car.  Agr.  Exp.  Sta. 

t  Diabroiica  vittata  Fab.  Family  Chrysomelidne.  See  F.  H.  Chittenden, 
Farmers'  Bulletin,  1038,  U.S.  Dept.  Agr.;  T.  J.  Headlee,  20th  Report  N.  H. 
Agr.  Exp.  Sta.,  p.  499. 

340 


INSECTS  INJURIOUS  TO  MELONS,  CUCUMBERS,  Etc.      341 


this  season  they  seem  to  feed  on  ahnost  anything,  as  they 
have  been  observed  feeding  on  a  long  hst  of  food-plants,  frequent- 
ing flowers  whose  petals  are  eaten.  As  soon  as  squash,  melons, 
or  cucumbers  break  through  the  soil,  they  gather  upon  them 
and  refuse  all  other  food.  If  the  foliage  is  covered  with  any 
offensive  substance  they  will  seek  out 
spots  which  have  not  been  reached  and 
feed  upon  them,  which  fact  is  of  im- 
portance in  considering  remedies.  After 
feeding  upon  cucurbs  for  a  few  days  the 
beetles  pair  and  the  females  commence 
to  deposit  eggs.  The  eggs  are  deposited 
singly  and  are  merely  dropped  in  crev- 
ices of  the  soil  or  in  the  opening  around 
the  stem  of  the  plant.  The  egg  is  oval, 
about  one-fortieth  inch  long,  bright  yel- 
low, and  sculptured  with  microscopic 
hexagonal  pits.  A  female  lays  about 
one  hundred  eggs  during  a  period  of  a 
month,  and  they  hatch  in  about  eight 
days  at  a  mean  temperature  of  74°  F. 
The  larva  is  a  slender,  white,  worm-like 
grub,  about  three-tenths  inch  long,  with 
dark-brown  head  and  anal-plate,  and  lighter  brown  thorax.  The 
larvae  bore  into  the  roots,  often  tunneling  into  the  base  of  the  stem, 
and  sometimes  mine  into  melons  lying  on  damp  soil.  Rarely  does 
injury  by  the  larvae  become  noticeable,  though  we  have  observed 
whole  patches  of  cucumber  and  melon  vines  killed  by  them,  which 
seems  remarkable,  considering  the  immense  numbers  of  the  beetles 
which  must  give  rise  to  many  times  more  larvae.  The  larva 
becomes  full  grown  in  about  a  month  and  then  forms  a  delicate 
earthen  cell  just  below  the  surface  of  the  soil  and  in  it  transforms 
to  the  whitish  pupa,  from  which  the  beetle  emerges  in  from  one  to 
two  weeks,  according  to  the  temperature.  In  southern  New 
Hampshire  the  beetles  emerge  from  the  last  of  August  to  the  first  of 
October,  the  complete  life  cycle  requiring  from  seven  to  nine  weeks, 
there  being  but  one  generation  a  year,  and  this  seems  to  be  true 
in  New  York.  In  Kentucky  the  complete  cycle  requires  but 
thirty-nine  days,  and  in  the  District  of  Columbia  newly  emerged 


Fig.  288. —  Larva  of  strip- 
ed cucumber  beetle  at 
work  in  cucumber  stem. 
(Photo  by  Headlee.) 


342       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

beetles  are  found  by  mid-July,  so  that  there  are  undoubtedly  two 
generations  in  that  latitude,  as  the  beetles  have  been  found  pairing 
and  with  well-developed  eggs  in  Delaware,  August  1st.  In  the 
latter  part  of  the  season  the  beetles  feed  on  the  blossoms  and 
pollen,  particularly  of  squash,  rarely  touching  the  foliage.  With 
the  first  frosty  nights  they  seek  shelter  under  the  fallen  leaves  and 
enter  hibernation  with  the  first  killing  frosts. 

Control — For  a  few  plants  or  where  the  beetles  are  unusually 
abundant,  coverings  of  netting  have  long  been  used  to  protect 
the  plants.       A  barrel  hoop  cut  in  two,  crossed,  and  the  ends 

_^,       -^^^   ^-TBK-^ r— ^T,-..srsr"      fastcued    to  another  hoop, 

.^  ^  J    /-^''  '  ■     ^2v^€V    ,      and  the  whole  then  covered 

with  netting,  makes  an 
admirable  cover,  often  sold 
by  dealers.  Two  stout  wires 
bent  into  arches  and  crossed, 
may  also  be  covered  with 
netting,  the  lower  edge  of 
w^hich  is  held  by  earth 
packed  over  the  edges.  Or 
cone-shaped  covers  may  be 
fashioned  out  of  wire  screen- 
FiG.  289.— Wire  screen  covei  iui  3  uLiiig  ing  and  kept  from  year  to 
cucurbs.     (After  Headlee.)  yg^^.^     (SeeHeadlee,  I.e.) 

Many  growers  obviate  loss  of  plants  and  the  necessity  of 
replanting  by  sowing  the  seed  in  rows  rather  thickly  and  then 
thinning  out  to  the  desired  distance  after  the  worst  injury  by  the 
beetle  is  passed.  Others  make  several  plantings  in  each  hill  at 
intervals  of  a  week,  but  the  former  plan  will  ensm'e  earlier  growth. 

The  growing  of  rows  of  early  beans  to  act  as  a  trap-crop  has 
been  suggested,  as  the  beetles  will  gather  on  them,  it  is  said,  and 
having  an  abundance  of  food  will  not  injure  the  cucurbits.  Squash 
may  be  effectively  used  in  this  way  as  the  beetles  are  peculiarly 
fond  of  the  quick-growing  squash  seedlings.  A  week  or  ten  days 
before  the  regular  crop,  plant  rows  of  squash  seed  around  and 
through  the  prospective  field,  and  plant  more  rows  when  the  regu- 
lar crop  is  planted.  If  the  main  crop  be  kept  well  dusted  or 
sprayed  as  advised  below,  the  beetles  will  concentrate  on  the  trap- 


INSECTS  INJURIOUS  TO  MELONS,  CUCUMBERS,  Etc.      343 

squash  and  might  be  destroyed  upon  it  by  spraying  with  pure 
kerosene. 

Liberal  fcrtihzation  with  quick-acting  fertiHzers  will  aid  the 
young  plants  to  make  a  quick  growth  and  thus  outgrow  the  injury. 

Growers  have  long  known  that  if  the  plants  are  kept  thoroughly 
covered  with  some  sort  of  dust  that  the  beetles  will  not  molest 
them,  and  various  sprays  have  been  used  in  the  same  way.  To  be 
effective,  the  plants  must  be  dusted  in  early  morning  while  the 
dew  is  on  and  all  parts  of  the  plant,  above  and  below,  must  be 
thoroughly  covered.  This  must  be  repeated  as  often  as  the  dust 
is  washed  or  blown  off,  or  the  plant  outgrows  it.  Air-slaked  lime 
mixed  with  sulfur,  tobacco  dust,  and  bug-death  have  been  the  most 
effective,  though  similar  powders  will  be  found  beneficial.  Bor- 
deaux mixture  has  been  recommended  for  this  purpose,  but  seems 
to  have  a  stunting  effect  on  the  young  plants.  The  most  valuable 
repellant  seems  to  be  a  spray  of  arsenate  of  lead  3  to  5  pounds  per 
barrel.  This  not  only  repels  the  beetles  better  than  any  other 
substance  tested  by  Dr.  Headlee  but  also  kills  many  which  are 
forced  to  feed  upon  it.  Arsenite  of  lime  and  zinc  arsenite  are 
both  recommended  by  Dr.  Chittenden,  (I.e.)  to  be  used  as  is  the 
lead  arsenate,  either  with  or  without  Bordeaux  mixture.  Most 
evidence  now  available  indicates  that  these  poisons  will  pro- 
tect the  vines  to  a  rather  limited  extent  and  too  much  reliance 
must  not  be  placed  upon  them.  They  are  of  value  when  used  in 
connection  with  the  cultural  methods  outlined.  The  problem 
of  cucumber  beetle  control  is  one  which  needs  more  investigation, 
in  spite  of  the  fact  that  the  insect  has  long  been  known. 

Various  repellants,  such  as  kerosene,  turpentine,  naphthalene 
or  moth  balls,  and  other  similar  odoriferous  substances,  have 
been  strongly  recommended,  but  careful  tests  have  not  demon- 
strated their  efficiency. 

It  is  evident  that  the  cleaning  up  of  vines  as  soon  as  the  crop 
can  be  gathered  and  the  destruction  of  all  refuse  will  deprive  the 
beetles  of  food  in  the  fall  and  force  them  to  seek  other  hibernating 
places,  thus  increasing  the  mortality. 

The  spotted  cucumber-beetle,  Diabrotica  12-punctata  Oliv., 
is  found  almost  always  with  the  striped  beetle  and  injures  the 
plants  in  the  same  way.  A  full  account  of  it  will  be  found  in  the 
chapter  dealing  with,  insects  affecting  the  corn  plant. 


344       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Melon-aphis  * 

Just  as  the  vines  commence  to  run,  a  plant  will  be  found  here 
and  there  with  the  foliage  curled  up  and  wilting  and  within  will  be 
found  masses  of  the  greenish  "  melon  lice,"  which  have  caused  the 
injury  by  their  many  beaks  sucking  out  the  sap  of  the  plant.  If 
allowed  to  multiply  unchecked  and  their  natural  enemies  do  not 
prevent  their  increase,  they  will  sometimes  become  so  abundant 


Fig  290. — The  melon  aphis  (Aphis  gossijpii  Glov.):  a,  winged  female;  aa„ 
enlarged  antenna  of  same;  ab,  dark  female,  side  view,  sucking  juice 
from  leaf;  b,  young  nymph;  c,  last  stage  of  nymph  of  winged  form;  d, 
wingless  female — greatly  enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

as  to  completely  ruin  a  whole  crop  just  as  the  melons  are  com- 
mencing to  ripen.  It  is  one  of  the  worst  pests  of  cucurbs  and  one 
which  requires  constant  vigilance  on  the  part  of  the  grower. 

The  aphids  are  to  be  found  on  various  weeds  in  early  spring 
and  appear  on  cucurbs  soon  after  they  start  growth.  Both  winged 
and  wingless  females  occur  throughout  the  year.     The  wingless 

*  Aphis  gossypii  Glover.  Family  Aphididce.  See  F.  H.  Chittenden, 
Farmers'  Bulletin  914,  U.  S.  Dept.  Agr.  ;  also  C  E.  Sanborn,  Bulletin  98, 
Oklahoma  Agr.  Exp.  Sta.,  and  C.  E.  Dursh,  Bulletin  174,  Illinois  Agr.  Exp. 
Sta. 


INSECTS  INJURIOUS  TO  MELONS,  CUCUMBERS,  Etc.    345 

form  is  about  one-fifteenth  inch  long  and  varies  from  Hght  yellow 
or  tan  colored  to  deep  olive-green  or  deep  green  which  appears 
almost  blackish,  the  abdomen  being  always  more  or  less  mottled. 
The  rather  long,  tapering  honey-tubes  are  jet-black,  and  the  legs 
and  antennae  pale  whitish-yellow.  The  young  nymphs  always 
show  a  distinct  yellowish-brown  or  pale  salmon-colored  area  just 
in  front  of  the  honey-tubes  and  a  dark  transverse  band  between 
them.  The  nymphs  of  the  last  stage,  in  which  the  wing  pads  are 
visible,  are  marked  on  the  back  with  little  flecks  of  silvery  white, 
waxy  bloom.  The  winged  female  is  about  the  same  length  and  the 
wings  expand  one-fifth  to  one-quarter  inch.  The  color  varies  as 
in  the  wingless  form,  but  there  are  black  spots  along  the  sides 
of  the  abdomen,  and  the  head  and  thorax  are  dark  as  shown  in 
the  above  figure. 

The  melon-aphis  is  found  throughout  the  country  southward 
through  Central  America,  and  though  it  often  does  serious  damage 
in  the  North  it  is  worse  in  the  South.  It  has  a  long  list  of  food 
plants,  among  the  crops  injured  by  it  being  all  the  cucurbs,  cotton, 
okra,  orange,  and  its  occasional  food-plants  include  many  others, 
as  it  is  found  on  a  long  list  of  weeds,  most  abundantly  on  shep- 
herd's purse  and  pepper-grass,  upon  which  it  multiplies  in  early 
spring  and  probably  passes  the  winter. 

Life  History. — The  life  history  is  much  the  same  as  that  of  most 
of  our  common  aphids,  though  of  some  phases  we  are  still  in 
ignorance  in  spite  of  the  most  careful  study.  The  females  give 
birth  to  from  four  to  ten  aphids  a  day,  depending  upon  the  tem- 
perature and  food  supply,  and  these  become  full  grown  in  from  six 
to  eight  days.  As  the  affected  leaf  becomes  non-succulent  the 
aphids  migrate  to  another  leaf  and  often  cluster  on  the  terminal 
which  is  checked  and  stunted.  As  they  become  more  numerous, 
winged  forms  migrate  to  other  plants  and  within  two  weeks  a 
colony  of  fift}^  or  more  will  form  the  progeny  of  every  one  born 
by  the  immigrating  female.  Reproduction  seems  to  go  on  this 
way  throughout  the  year,  being  stopped  only  by  the  cold  of  win- 
ter, as  far  as  has  been  observed.  No  true  sexual  forms  or  eggs,  as 
are  known  to  occur  with  other  nearly  related  species,  have  been 
observed,  and  the  viviparous  forms  have  been  found  throughout 
the  winter  in  Colorado  and  Texas. 


346         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Enemies. — Fortunately  the  melon-aphis  is  subject  to  the  unre- 
mitting attack  of  many  insect  enemies,  the  list  including  some 
thirty-five  species.     Among  the  more  important  are  the  common 


Fig.  291. — Melon  aphids  on  cotton  leaf  which  have  been  killed  by  parasites. 


INSECTS  INJURIOUS  TO  MELONS,  CUCUMBERS,  Etc.    347 

ladybird-beetles  and  their  larvae,  of  which  the  convergent  lady- 
bii'd,*  the  nine-spotted  ladybird,!  and  the  spotted  ladybird, J 
shown  in  Figs  1-5,  are  among  the  most  effective,  and  the  maggots 
of  various  cominon  syrphiis-fiies,  and  the  aphis-Hons.§  Even 
more  beneficial  are  the  little  parasitic  flies  whose  larvae  live  within 
the  maggots  and  destroy  myriads  of  them  with  incredible  swift- 
ness. The  most  common  of  these H  are  the  same  as  the  most 
common  parasite  of  the  green  bug  (Fig  120),  and  they  often  destroy 
the  aphid s  over  a  whole  field  in  a  few  days.  They  are  most  effect- 
ive in  bright,  warm  weather,  when  they  reproduce  most  rapidly, 
but  in  cool,  moist  weather  they  reproduce  but  slowly,  and  if  such 
a  summer  follows  similar  weather  conditions  during  the  spring,  the 
aphids  multiply  rapidly  without  a  corresponding  increase  of  their 
enemies  and  serious  damage  results.  Inasmuch  as  these  same 
enemies  attack  the  cabbage-aphis,  Professor  C.  E.  Sanborn*  has 
suggested  that  the  cabbage-aphis  might  be  encouraged  to  multiply 
on  crops  planted  near  melons  or  cucumbers,  so  that  an  abundance 
of  parasites  and  insect  enemies  might  be  in  readiness  to  attack  the 
melon-aphis  when  it  appears.  This  might  be  done  by  planting 
kale,  rape,  or  wild  mustard  in  the  fall,  upon  which  the  cabbage- 
aphids  will  pass  the  winter  and  will  multiply  in  early  spring. 
This  trap  crop  should  be  planted  in  rows  around  the  prospective 
melon-field,  and  if  the  latter  be  large,  rows  should  be  planted 
through  it.  If  the  kale  does  not  soon  become  infested  with  the 
cabbage-aphis,  transport  some  from  the  nearest  cabbage-patch. 
The  ladybirds  and  parasites  multiply  rapidly  with  plenty  of  the 
cabbage-aphids  for  food,  and  as  soon  as  the  food  supply  becomes 
scarce  they  are  forced  to  migrate  and  will  search  out  any  colonies 
of  melon-aphids.     This  method  has  not  come  into  general  use. 

Control. — The  most  important  factor  in  the  control  of  this, 
as  well  as  many  other  aphids,  is  constant  watchfulness,  inspect- 
ing the  plants  frequently  and  destroying  badly  infested  individual 
plants  and  treating  small  areas  before  the  pest  becomes  spread 
throughout  the  crop. 

*  Hippodamia  convergens  Guer. 
t  Coccinella  9-notata  Herbst. 

i  Megilla  maculata  DeG.     Family  Coccinellidce. 

§  Family  Chrysopidce. 

^  Lysiphlebus  testaceipes  Cress.     Family  Braconidce. 

*  See  Bulletin  89,  Texas  Agr.  Exp.  Sta.,  p.  44. 


348       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Where  a  few  young  plants  are  affected  or  before  the  leaves  have 
become  badly  curled,  the  aphids  may  be  destroyed  by  spraying 
with  kerosene  emulsion,  containing  5  to  8  per  cent  kerosene, 
whale-oil  soap,  1  pound  to  5  gallons  of  water,  or  tobacco  extracts, 
the  latter  having  given  best  results  in  recent  tests.  Emulsion 
must  be  carefully  made  or  burning  will  result.  The  aphids  must 
be  hit  to  destroy  them,  and  it  is  necessary  to  use  an  underspray 
nozzle  (page  73),  or  to  turn  the  vines  over  and  then  return  them, 
so  that  all  the  insects  may  be  covered.  After  the  foliage  is  well 
curled  it  is  practically  impossible  to  reach  the  aphids  by  spraying. 

Fumigation  with  carbon  bisulphide  and  tobacco  preparations 
has  been  extensively  tested  and  recommended.  It  has  not  been 
found  practical  on  a  large  scale  and  there  has  been  some  tendency 
to  injure  the  plants  in  the  process,  both  by  the  action  of  the 
fumes  and  by  the  handling  necessary  to  get  the  larger  vines  under 
the  fumigating  frames.  For  this  reason  it  is  now  considered  of 
doubtful  value  under  any  circumstances  and  is  not  recommended. 

If  the  vines  are  watched  carefully  and  sprayed  with  "  Black- 
leaf  40  "  at  the  first  appearance  of  the  plant-lice,  the  matter  of 
control  will  be  found  to  be  relatively  simple,  and  this,  along  with 
the  cultural  methods  suggested,  is  the  only  treatment  that  will  be 
found  practical  for  the  growers  generally.  Other  spray  solutions, 
or  mixtures  such  as  kerosene  emulsion  or  whale-oil  soap,  may, 
of  course,  be  substituted  for  the  tobacco  with  about  the  same 
results. 

The  Squash-bug  * 

About  the  time  the  vines  begin  to  run  a  wilted  leaf  is  found 
here  and  there  which  examination  shows  to  be  due  to  the  common 
brownish-black  squash-bug.  If  search  be  made  in  early  morning, 
the  bugs  will  usually  be  found  secreted  under  clods  of  earth,  or 
whatever  rubbish  may  be  near  the  vines.  They  are  about  three- 
quarters  inch  long,  and  too  well-known  to  need  other  description. 

Life  History. — For  the  next  month  or  six  weeks  the  females 

deposit  their  eggs,  mostly  on  the  under  sides  of  the  leaves.  They 

are    oval,    about    one-sixteenth    inch    long,    laid    in    irregularly 

shaped  clusters.     When  newly  laid  they  are  pale  yellow-brown, 

*  Anasa  tristis  DeG.  Family  Coreidce.  See  Weed  and  Conradi,  Bulletin 
89,  N.  H.  Agr.  Exp.  Sta.;  F.  H.  Chittenden,  Circular  39,  Div.  Ent.,  U.  S. 
Dept.  Agr. 


Fig.  292. — Squash-bugs  and  nymi)lis  at  work  on  young  plant — natural  size. 

349 


350      INSECTS  INJURIOUS  TO  MELONS,  CUCUMBERS,  Etc. 


but  this  soon  grows  darker,  so  that  the  stage  of  their  development 
may  be  told  by  the  color.  In  from  six  to  fifteen  days,  depending 

upon  the  temperature,  the 
eggs  hatch.  The  young 
nymphs  are  brilliantly  col- 
ored, the  antennae  and  legs 
being  bright  crimson,  the 
head  and  anterior  thorax  a 
lighter  crimson,  and  the  pos- 
terior thorax  and  abdomen  a 
bright  green,  but  in  a  little 
while  the  crimson  changes  to 
a  jet  black.  The  young  bugs 
remain  near  each  other,  suck- 
ing the  juices  from  the  foli- 
age and  soon  causing  the 
leaves  to  wither.  During 
their  growth,  which  requires 
four  to  five  weeks,  they 
moult  some  five  times.  The 
adult  bugs  appear  in  August, 
but  in  the  North  they  neither  mate  nor  lay  eggs  that  season,  but 
feed  until  frosts  blacken  the  leaves,  when  they  disappear  into  winter 


Fig.  293. — Eggs  of  the  squash-bug — en- 
larged.    (Photo  by  R.  I.  Smith.) 


Fig.  294. — The  squash-bug;  a,  ma- 
ture female;  h,  side  view  of  head 
showing  beak;  c,  abdominal  seg- 
ments of  male;  d,  same  of  female; 
a,  twice  natural  size;  h,  c,  d,  more 
enlarged.  (After  Chittenden,  U.  S. 
Dept.  Agr.) 


Fig.  295. — The  squash-bug:  adult  at 
left,  and  different  stages  of  nymphs 
— about  VA  times  natural  size. 
(Photo  by  Quaintance.) 


INSECTS  INJURIOUS  TO  MELONS,  CUCUMBERS,  Etc.     351 

quarters,  hibernating  along  the  edge  of  woodlands,  beneath  leaves, 
under  logs,  boards  or  whatever  shelter  may  be  available.  In 
the  South  there  are  probably  two  or  three  broods  a  year  accord- 
ing to  the  latitude. 

Control. — The  eggs  are  easily  seen  and  should  be  picked  off 
and  destroyed.  The  adults  cannot  be  killed  by  insecticides,  but 
the  nymphs  may  be  destroyed  liy  spraying  with  kerosene  emulsion, 
or  a  mixture  of  "  Black-leaf  40,  "  one  to  400  with  soap.  The 
adult  bugs  may  be  readily  trapped  by  placing  small  pieces  of 
board  or  similar  shelter  near  the  vines,  under  which  they  will 
hide  at  night  and  from  which  they  may  be  gathered  in  the  early 
morning.  Cucumbers  and  melons  may  be  protected  by  planting 
early  squash  among  them,  as  the  bugs  prefer  the  squash,  from 
which  they  may  be  collected.  Cleaning  up  the  vines  in  the  fall 
is  evidently  of  importance  in  reducing  the  number  which  will 
hibernate 

The  Squash  Ladybird  * 

Although  almost  all  of  the  ladybird  beetles  are  exceedingly 
beneficial,  this  species,  with  its  near  relative  the  bean-ladybird 


FiQ.'^296. — ^The  squash  ladybird  (Epilachna  borealis  Fab.):  a,  larva;  b,  pupa; 
c,  adult  beetle — three  times  natural  size;  d,  egg — four  times  natural 
size;  e,  surface  of  egg  highly  magnified.  (After  Chittenden,  U.  S. 
Dept.  Agr.) 

are  the  exceptions  which  prove  the  rule,  being  the  only  injurious 

forms  with  which  we  have  to  contend.     Both  the  beetles  and  larvse 

feed  on  the  foliage  of  various  cucurbs,  but  prefer  that  of  the  squash. 

It  is  an  Eastern  species,  not  being  injurious  west  of  the  Mississippi 

*  Epilachna  borealis  Fab.  Family  Coccinellidce.  See  F.  H.  Chittenden, 
Bulletin  19,  n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr.;  J.  B.  Smith,  Bulletin  94,  N.  J. 
Agr.  Exp.  Sta. 


352         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


and  being  most  troublesome  in  the  Middle  Atlantic  States.  The 
beetle  is  nearly  hemispherical  in  shape,  slightly  oval,  about  one- 
third  inch  long,  yellowish  or  reddish-brown,  marked  with  seven 
black  spots  on  each  wing-cover  and  four  smaller  ones  on  the 
thorax  as  shown  in  Fig.  296. 

Life  History. — The  life  history,  as  given  by  Dr.  Chittenden  for 
the  District  of  Columbia  and  northward,  is  as  follows:  "  The 
insect  hibernates  in  the  adult  condition  under  bark  or  other 
convenient  shelter  and  appears  abroad  sometime  in  May  or 
June.     Egg  deposition  has  been  observed  in  the  latter  part  of 

June,  and  there  is  evidence  that 
the  eggs  are  deposited  also  much 
later."  The  eggs  are  about  three- 
tenths  inch  long,  elongate  oval 
of  a  yellow  color,  and  laid  in  irreg- 
ular clusters  of  from  12  to  50. 
"  They  hatch  in  from  six  to  nine 
days,  and  the  larvae  begin  to  feed 
at  once  on  the  leaves,  causing 
them  to  wither  and  die."  The 
larva  is  yellow,  with  six  rows  of 
black  branching  spines,  and  is 
about  one-half  inch  long  when 
grown.  ''The  larva  attains  full 
development  in  from  two  to  four 
weeks,  ceases  feeding,  and  attaches 
itself  by  its  anal  extremity  to 
a  leaf,  and  next  day  sheds  its 
larval  skin,  which  is  pushed  down 
toward  the  end  of  the  body,  when  the  pupa  stage  is  assumed.  The 
larva  matures  anytime  from  the  middle  of  July  to  near  the  middle 
of  September,  In  the  pupa  state  the  insect  remains  from  six  to 
nine  days,  when  the  skin  separates  down  the  back  and  the  perfect 
beetle  emerges,  the  new  brood  appearing  as  early  as  the  last  of 
July.  After  feeding  for  some  time  the  beetles  disappear  for  hiber- 
nation, .  .  .  beginning  about  the  middle  of  September."  The 
adults  have  the  habit  of  marking  out  a  circular  area  of  the  leaf, 
which  seems  to  cause  the  tissue  to  wilt,  and  then  feeding  within 


Fig.  297. — Work  of  the  squash  lady- 
bird—  greatly  reduced.  (After  W. 
E.  Britton.) 


INSECTS  INJURIOUS  TO  MELONS,  CUCUMBERS,  Etc.    353 

this  area.    The  larvae  are  to  be  found  feeding  on  the  under  surface  of 
the  fohage  in  July  and  August. 

Control. — Usually  hand  picking  the  beetles  and  eggs  will 
control  the  pest,  but  if  abundant  it  may  be  readily  destroyed  by 
spraying  or  dusting  with  arsenicals. 


The  Squash-vine  Borer  * 

In  many  localities  the  most  serious  pest  of  squash  is  the 
Squash-vine  Borer,  and  although  other  cucurbs  are  sometimes 
injured,  they  are  relatively  free  from  attack  if  squash  or  pumpkins 


Fig.  298. — The  squash-vine  borer  (Melittia  satyriniformis  Hbn.):  a,  male 
moth;  b,  female  with  wings  folded  at  rest;  c,  eggs  shown  on  bit  of  stem; 
d,  full-grown  larva  in  vine;  e,  pupa;  /,  pupal  cell — all  one-third  larger 
than  natural  size.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

are  present.  The  larvae  bore  in  the  stems,  causing  them  to  rot 
where  affected,  so  that  they  break  off  and  the  plant  wilts  and  dies. 
The  presence  of  the  borer  is  indicated  by  the  coarse  yellowish 
excrement  which  it  forces  from  its  burrow  and  which  is  found 
on  the  ground  beneath,  and  by  the  sudden  wilting  of  the  leaves. 
Injury  is  most  severe  at  the  base  of  the  vine,  which  gradually 
decays,  so  that  it  is  severed  and  the  whole  plant  dies.  A  half- 
dozen  or  more  larvae  are  often  found  in  a  single  stem,  and  as  many 
as  forty  have  been  taken  from  one  vine,  the  larvae  attacking  all 
parts  of  the  vine  and  even  the  petioles  and  large  ribs  of  the  leaves 
when  abundant.  Injury  is  worst  on  Hubbard,  marrow,  cymlings 
and  late  varieties  of  squash. 

*  Melittia  satyriniformis  Hbn.     Family  Sesiidoe.    Farmers'  Bulletin  668, 
U.  S.  Dept.  Agr. 


354    INSECTS  INJURIOUS  TO  MELONS,  CUCUMBERS,  Etc. 


The  adult  is  one  of  the  clear-winged  moths  with  a  wing  expanse 
of  about  Ij  inches,  the  fore-wings  being  opaque,  dark  olive 
green  in  color,  with  a  metallic  lustre  and  a  fringe  of  brownish 
black.  The  hind-wings  are  transparent,  with  a  bluish  reflection, 
and  the  veins  and  marginal  fringe  black.  The  abdomen  is  marked 
with  orange,  or  red,  black  and  bronze,  and  the  legs  are  bright 
orange,  with  tarsi  black  with  white  bands.  The  species  occurs 
throughout  the  states  east  of  the  Rockies  and  southward  into 
Central  and  South  America. 


Fig.  299. — A  squash  stem  cut  open  showing  borers  within.     (Photo 
by  Quaintance.) 

Life  History. — The  moths  appear  soon  after  their  food-plants 
start  growth,  from  mid-April  along  the  Gulf  Coast  to  June  1st, 
in  New  Jersey,  and  late  June  or  early  July  in  Connecticut.  They 
fly  only  in  the  daytime,  and  their  clear  wings  and  brightly  marked 
bodies  give  them  a  close  resemblance  to  large  wasps.  The  eggs 
are  laid  on  all  parts  of  the  plant,  but  chiefly  on  the  stems,  par- 
ticularly near  the  base.  The  oval  egg  is  of  a  dull  red  color  and 
about  one-twenty-fifth  inch  long.  The  moth  deposits  her  eggs 
singly,  and  one  individual  has  been  observed  to  lay  as  many  as 
212.  They  hatch  in  one  or  two  weeks.  The  young  larva  enters 
the  main  stem  and  tunnels  through  it,  and  often  enters  the  leaf- 


INSECTS  INJURIOUS  TO  MELONS,  CUCUMBERS,  Etc.    355 

petioles  branching  from  it.  It  is  a  soft,  stout,  whitish  caterpillar, 
with  a  small  black  head,  and  about  one  inch  long  when  full  grown. 
The  larvae  reach  maturity  in  about  four  weeks  and  then  enter 
the  earth,  where  they  make  tough  silken  cocoons,  coated  with 
particles  of  earth,  an  inch  or  two  below  the  surface.  In  the 
South  the  larvse  transform  to  pupae  from  which  a  second  generation 
of  moths  emerges  in  late  July,  but  in  the  North  the  larvae  hibernate 
in  the  cocoons  over  winter,  and  transform  the  next  spring.  The 
pupa  is  about  five-eighths  inch  long,  dark  brown,  and  with  a 
horn-like  process  on  the  head  between  the  eyes.  By  the  aid 
of  this  the  pupa  cuts  open  one  end  of  the  cocoon  and  with  the 
hook-like  spines  on  the  abdomen  wriggles  to  the  surface  of  the 
earth  before  transforming  to  the  moth.  As  indicated,  there  is 
but  one  generation  in  the  North,  a  partial  second  brood  in  the 
latitude  of  New  Jersey  and  the  District  of  Columbia,  and  two 
full  generations  in  the  South. 

Control. — As  the  larvae  work  within  the  vines,  insecticide 
treatment  is  useless,  and  the  pest  must  be  controlled  by  methods 
of  culture. 

Obviously  the  vines  should  be  raked  up  and  destroyed  as 
soon  as  the  crop  is  gathered,  so  as  to  destroy  all  of  the  borers 
within  them.  As  the  larvae  or  pupae  hibernate  over  winter  in 
the  soil,  it  has  been  found  that  frequent  light  harrowing  in  the 
fall  will  bring  them  to  the  surface,  and  that  deep  plowing  in  the 
early  spring  will  then  bury  any  surviving  so  that  the  moths 
cannot  emerge.  Rotation  of  the  crop  will  evidently  decrease  the 
number  of  moths.  Where  the  pest  is  abundant  late  squash  may 
be  protected  by  planting  rows  of  early  summer  squashes  as  soon 
as  possible.  These  will  attract  the  moths  so  that  there  will  be 
relatively  few  eggs  deposited  on  the  main  crop  planted  later.  As 
soon  as  the  early  crop  is  gathered,  or  as  soon  as  it  becomes  well 
infested,  if  it  is  used  only  for  a  trap,  the  vines  should  be  raked 
up  and  burned  so  as  to  destroy  all  eggs  and  larvae.  It  is  well 
to  cover  the  vines  with  earth  one  or  two  feet  from  the  base  so 
as  to  induce  the  growth  of  secondary  roots,  which  will  support 
the  plant  in  case  the  vine  is  severed  lower  down.  The  old- 
fashioned  method  of  slitting  the  vines  with  a  knife  and  thus 
killing  the  borers  is  about  the  only  means  of  destroying  them 
after  they  have  become  estabhshed.    The  position  of  a  borer  may 


356         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


be  detected  by  the  excrement  extruded  from  its  burrow, 
and  if  the  wound  be  covered  with  moist  earth  it  will  assist  the 
healing.     Destroy  the  parent  moths  whenever  they  are  seen. 


Fig.  300. — The  pickle  worm  (Diaphania  nitidalis  Cramer) :  larva,  pupa,  and 
adult — all  enlarged.     (Photos  by  Quaintance.) 

The  Pickle  Worm  * 

The  pickle  worm  is  so  called  because  it  was  first  noted  as 

injuring  cucumbers  grown  for  pickling,  but  in  the   Gulf  States, 

where  it  is  most  injurious  it  is  more  commonly  a  pest  of  melons, 

*  Diaphania  nitidalis  Cramer.  Family  Pi/raustiflnp..  See  A.  L.  Quaint- 
ance, Bulletin  54,  Ga.  Agr.  Exp.  Sta.,  R.I.  Smith,  Bulletin  214,  N.  C.  Agr. 
Exp.  Sta. 


INSECTS  INJURIOUS  TO  MELONS,  CUCUMBERS,  Etc      357 

and,  with  the  following  species,  with  which  it  is  often  confused, 
is  often  known  as  the  "  melon  worm."  Injury  in  the  Middle 
States  occurs  only  periodically,  though  it  has  been  noted  in 
Illinois  and  southern  Michigan,  but  in  the  Gulf  States  it  is  always 
a  serious  pest  of  all  the  cucurbs,  destroying  the  blossoms,  mining 
the  stems,  and  boring  into  the  ripening  fruit. 

The  moth  has  a  wing  expanse  of  about  Ij  inches,  is  yellowish- 
brown  with  a  purplish  iridescence,  and  is  readily  recognized  by 
an  irregular  yellowish  transparent  spot  on  the  middle  of  the 
fore-wings,  and  the  basal  half  of  the  hind-wings  of  the  same  color. 
The  abdomen  terminates  in  a  conspicuous  brush  of  large  blackish 
scales. 

Life  History. — The  moths  emerge  in  late  spring  and  deposit 
the  eggs  either  singly  or  in  clusters  of  3  to  8  on  the  flowers,  buds, 
or  tender  terminals.  The  yellowish-white  egg  is  about  one- 
thirtieth  inch  long,  and  rather  elliptical.  The  first  larvae 
are  to  be  found  in  Georgia  by  the  middle  of  June.  The  young 
larvae  which  hatch  from  eggs  laid  on  the  terminals  bore  into 
stems  and  leaves  and  later  often  tunnel  out  the  vines  like  the 
squash-vine  borer.  Those  from  eggs  laid  on  the  blossoms  usu- 
ally feed  in  the  blossoms,  and  a  half-dozen  may  often  be  found 
feeding  in  single  squash  blossoms,  for  which  they  seem  to 
have  a  decided  preference.  As  they  grow  older  the  larvae 
warder  from  one  plant  to  another,  often  boring  into  several 
fruits.  The  older  larvae  bore  into  the  fruit,  the  excrement  being 
pushed  out  from  the  orifice  and  later  accumulating  in  the  cavity 
within.  A  single  larva  boring  into  the  rind  will  do  sufficient 
injury  to  start  decay  and  ruin  the  fruit,  and  often  a  half- 
dozen  or  more  will  be  found  in  a  single  melon.  Until  half  grown 
the  larvae  are  marked  with  transverse  rows  of  black  spots.  The 
full-grown  larva  is  about  three-quarters  inch  long,  greenish 
or  yellowish-green,  with  head  and  prothoracic  shield  brown. 
The  larva  reaches  maturity  in  about  two  weeks,  when  a  thin 
silken  cocoon  is  made  in  the  fold  of  a  leaf  in  which  the  pupal 
stage  is  assumed,  which  occupies  about  a  week.  The  pupa  is 
one-half  to  one  inch  long,  brown,  with  wing  and  leg  sheaths 
lighter,  and  the  tip  of  the  abdomen  bears  a  group  of  short  curved 
spines  which  hold  the  pupa  more  securely  in  the  cocoon.     During 


358 


INSECT  PESTS  OF  FARM  GARDEN  AND  ORCHARD 


July  and  August  the  complete  life  cycle  requires  about  four  weeks 
in  Georgia,  and  at  least  three  definite  generations  have  been 
recognized,  the  injury  by  the  larvae  being  most  severe  in  July  and 
August,  evidently  by  the  second  generation.  The  winter  is  passed 
in  the  pupal  stage  in  the  foliage  or  trash  remaining  on  the  field. 
Control. — As  injury  is  worst  in  late  summer,  early  plantings  and 
early-maturing  varieties  are  but  little  injured.  The  thorough  de- 
struction of  the  vines,  foliage,  an'd 
trash  on  the  field  after  the  crop  is 
secured  is  of  the  utmost  import- 
ance in  controlling  this  as  well  as 
other  pests  of  cucurbs,  and  may 
probably  be  accomplished  with  this 
species  by  deeply  plowing  under  the 
refuse.  Professor  A.  L.  Quaint- 
ance,  to  whom  we  are  indebted  for 
our  knowledge  of  this  pest,  has 
found  that  the  moths  greatly  prefer 
to  oviposit  on  squash  and  that  it 
may  be  successfully  used  as  a  trap 
crop  for  the  protection  of  other  cu- 
curbs. Rows  of  summer  squash 
should  be  planted  through  the  cu- 
cumber or  melon  fields  as  early  as 
possible,  the  rows  being  planted 
every  two  weeks  so  there  will  be 
flowers  through  July.  The  squash 
bloom,  with  the  contained  larvse, 

■n,      oni      a        in  •  c    .  j  must  be  collected  and  destroyed  at 

Fig.  301. — Scjuasli  flower  infested  .  i  /-.  ,  •        i 

with  pickle  worms.     (Photo  by  frequent  mtervals.      Otherwise  the 
Quaintance.)  squash  will  merely  augment  the  in- 

jury, as  the  larvse  will  migrate  to  the  crop.  Careful  tests  of  this 
method  showed  almost  complete  protection  to  muskmelons.  The 
use  of  arsenicals  has  been  of  little  value  against  this  pest  as  far  as 
tested,  but  as  they  should  be  applied  to  control  the  next  species, 
may  be  of  some  incidental  value. 


INSECTS  INJURIOUS  TO  MELONS,  CUCUMBERS,  Etc.    359 


The  Melon  Caterpillar  * 

This  species  is  very  similar  to  the  last  in  life  history  and  habits 
and  is  very  commonly  confused  with  it.     It  seems  to  be  commonly 


Fig.  302. — Pickle  worms  at  work  on  a  cucumber.    (Photo  by  Quaintance.) 

injurious  only  in  the  Gulf  States,  though  the  moths  have  been  taken 
from  Canada  to  Central  America  and  injury  has  been  seen  in  Kansas. 
The  moth  is  a  beautiful  insect  with  wings  of  a  pearly  iridescent 
whiteness,  bordered  with  brown- 
ish-black and  expanding  about 
an  inch.  The  anterior  half  of 
the  thorax  and  head  is  the  same 
color  as  the  wing  border,  while 
the  abdomen  is  white,  tinged  with 
brownish  toward  the  tip,  which  is 
surmounted  by  a  brush  of  long 
dark  scales.  The  larvae  are  very 
similar  to  those  of  the  pickle 
worm,  and  the  life  history  so  far 
as  ascertained  seems  to  be  prac- 
tically the  same.  The  essential  difference  in  the  habits  of  this 
species  is  that  the  young  larvae  very  commonly  feed  on  the 
foliage.  Later  on  they  mine  mto  the  stems  and  fruit  and  are 
readily    confused  with  those  of  the  last  species. 

Control. — The  fact  that  the  young  larvae  feed  on  the  foliage 
makes    it    possible    to    destroy    them   with   arsenicals,    and    by 

*  Diaphania  hyalinata  Linn.  Family  Pyraustidce.  See  A.  L.  Quaintance, 
Bulletin  45,  Geo.  Agr.  Exp.  Sta.,  p.  42;  R.  I.  Smith,  Bulletin  214,  N.  C. 
Agr.  Exp.  Sta. 


Fig.  303.  —  The  melon- worm  moth 
(Diaphania  hyalinita  Linn.) — en- 
larged.    (Photo  by  Quaintance.) 


360 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


spraying  the  young  foliage  with  arsenate  of  lead  3  pounds  to  the 
barrel,  as  advised  for  the  striped  cucumber-beetle,  they  should 


Fig.  304. — The  melon-worm — enlargad.     (Photo  by  R.  I.  Smith.) 

be  readily  controlled.     The  cultural  methods  advised  for  the  con- 
trol of  the  last  species  will  of  course  be  equally  apphcable  for  this. 


CHAPTER  XIX 
MISCELLANEOUS  GARDEN  INSECTS 

The  Pale-striped  Flea-beetle  * 

Enormous  numbers  of  the  Pale-striped  Flea-beetles  often 
appear  in  late  June  or  early  July  and  nearly  ruin  the  young 
crops  they  may  attack  before  being  brought  under  control.  Such 
outbreaks  occur  only  periodically,  so  that  usually  the  grower  is 


Fig.  305. — The  pale-striped  flea-beetle  (Systena  blanda  Mels.):  a,  larva; 
b,  beetle;  c.  eggs;  d,  sculpture  of  egg;  e,  anal  segment  of  larva  from 
side;  /,  same  from  above;  a,  d,  six  times  natural  size;  e,  f,  more  en- 
lai  ged ;  g,  the  banded  flea-beetle  (Systena  tceniata  Say) — six  times  natural 
size.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

unprepared  to  cope  with  them,  which  is  true  of  the  appearance 
of  many  of  our  worst  insect  pests.  These  flea-beetles  are  almost 
omnivorous  as  regards  food,  for  although  particularly  injurious 
to  corn  and  tomatoes,  they  have  also  injured  beans,  beets,  pota- 
toes, egg-plant,  carrots,  melons  and  other  cucurbs,  turnips  and 
other  crucifers,  strawberry,  cotton,  oats,  peanuts,  pear  foliage,  etc., 

*  Systena  bianda  Mels.  Family  Chrysomelidce.  See  F.  H.  Chittenden 
Bulletin,  25,  n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr.,  p.  22;  S.  A.  Forbes,  18th 
Report  State  Ent.,  111.,  p.  21. 

361 


GARDEN  PLANT-LICE 


Fig.  306. — General  recommendations  and  information  concerning  plant-lice 
of  the  garden,  as  issued  by  the  Bureau  of  Entomology,  U.  S.  Dept.  Agr 

362 


INSECTS  INJURIOUS  TO  MISCELLANEOUS  CROPS         363 

and  many  common  weeds,  so  that  it  may  be  safely  said  that  when 
abundant  they  will  attack  almost  any  crop  at  hand.  The  species 
seems  to  occur  practicall}^  throughout  the  United  States,  but  injury 
has  been  most  common  in  the  Middle  States  east  of  the  plains. 

The  beetle  is  about  one-eighth  inch  long,  cream-colored,  with 
the  wing-covers  marked  with  three  stripes  of  dull  light-brown, 
and  the  eyes  and  abdomen  are  black.  A  nearly  related  species, 
the  banded  flea-beetle,*  is  very  similar  in  appearance,  the  dark 
stripes  being  expanded  until  it  is  a  poUshed  black  with  two  white 
stripes  (Fig.  3056),  and  the  two  species  have  until  recently  been 
commonl}'  considered  as  identical.  They  are  similar  in  life 
history  and  habits  so  far  as  known,  and  may  be  considered  as 
the  same  for  practical  purposes. 

Life  History . . — Very  little  is  known  of  the  life  history.  The 
beetles  usually  appear  in  late  June  and  early  July,  coming  out  in 
enormous  numbers,  gnawing  small  holes  in  the  foliage  of  the 
plants  attacked,  so  that  when  abundant  they  completely  defoUate 
the  plant  in  two  or  three  days  and  often  necessitate  replanting. 

Control. — The  destruction  of  the  weeds  on  which  the  larvae 
develop  is  of  obvious  importance,  and  it  would  be  well  to  plow 
under  deeply  any  fields  grown  up  in  weeds  during  late  summer. 
Bordeaux  mixture  is  possibly  the  best  repellant  for  these  beetles, 
though  they  will  be  driven  off  by  covering  the  plants  with  any 
dust  which  thoroughly  coats  the  foUage.  Usually  the  best  method 
will  be  to  spray  the  plants  thoroughly  with  Bordeaux  mixture 
containing  3  pounds  of  arsenate  of  lead  or  one-third  pound  Paris 
green  per  barrel.  All  parts  of  the  foliage  must  be  thoroughly 
coated.  Good  success  has  also  attended  dusting  the  plants  with 
Paris  green  and  flour  and  by  spraying  the  beetles  with  kerosene 
emulsion.  Powdered  arsenate  of  lead  dusted  over  the  foUage 
while  the  dew  is  on  would  probably  prove  effective,  or  it  might 
be  sprayed  at  the  rate  of  3  to  5  pounds  to  the  barrel. 

The  Garden  Webworm  f 

The  term  garden  webworm  is  possibly  a  misnomer,  for  although 
these  little  caterpillars  frequently  do  more  or  less  injury  to  various 

*  Systena  tceniata  Say. 

^  Loxostege  similalis  Gn.  Family  Pyraustidce.  See  C.  V.  Riley,  Report 
U.  S.  Comm.  Agr.  for  1885,  p.  265;  Sanderson,  Bulletin  57,  Bureau  of  Ento- 
mology, U.  S.  Dept.  Agr.,  p.  11. 


364 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


garden  crops  when  they  become  overabundant  and  migrate  to 
them  from  the  weeds  on  which  they  normally  feed,  and  occasionally 
do  some  damage  to  sugar  beets,  they  are  best  known  as  a  pest  of 
corn  and  cotton.  Though  the  species  occurs  throughout  the 
United  States  and  south  to  South  America,  it  has  been  most 
injurious  from  Nebraska  southward  and  east  to  Mississippi  and 
Illinois.  The  larvae  feed  normally  on  the  pigweed  or  careless 
weed  (Amaranthus  spp.)  from  which  they  sometimes  receive  the 
local  name  of  "careless  worm,"  and  only  when  they  become 
overabundant  on  these  weeds  do  they  usually  increase  sufficiently 
to  migrate  from  them  and  attack  crops. 

The  moth  is  a  yellowish,  buff  or  grayish-brown  color,  marked 
as  shown  in  Fig.  307,  and  with  a  wing  expanse  of  about  three- 
quarters  of  an  inch.  The  larva  also  varies  in  color  from  pale 
and  greenish-yellow  to  dark  yellow,  and  is  marked  with  numerous 
black  tubercles  as  shown  in  Fig.  307,  b,  c. 

Life  History. — The  hibernating  habits  are  not  known,  but  from 
analogy  with  the  beet  webworm,   and   the  appearance   of  the 

moths,  it  seems 
probable  that  the 
winter  is  passed  by 
the  larvae  or  pupae 
in  the  soil.  The 
moths  appear  in 
Texas  by  mid-April 
and  in  central  Illi- 
nois in  late  May 
and  early  June. 
The  yellowish  eggs 
are  laid  on  the  foli- 
age in  small  patches 
of  from  8  to  20  and 
The  larvae  of  the  first 


Fig.  307. — The  garden  webworm  (Loxostege  simi- 
lalis  Gn.) :  o,  male  moth;  b,  c  larvaj;  d,  anal 
segment  of  same;  e,  abdominal  segment  of  same 
from  side;  /,  pupa;  g,  tip  of  abdomen  of  same; 
a,  b,  c,  f,  somewhat  enlarged;  d,  e,  g,  more  en- 
larged. (After  Riley  and  Chittenden,  U.  S.  Dept. 
Agr.) 


in  Texas  hatch  in  three  or  four  days, 
generations  feed  on  weeds  or  alfalfa,  where  it  is  grown,  and  then 
migrate  to  corn  and  cotton  or  garden  truck,  the  former  crops 
being  attacked  when  six  or  eight  inches  high.  In  feeding  the 
caterpillars  spin  a  fine  web,  which  gradually  envelopes  the  plant, 
of  which  nothing  is  left  but  the  skeletons  of  the  leaves  when  the 


INSECTS  INJURIOUS  TO  MISCELLANEOUS  CROPS        365 


larvae  are  abundant.  The  larvae  become  full  grown  in  about 
three  weeks  in  summer,  when  they  descend  to  the  soil  and  pupate 
in  small  silken  cells  on  or  just  below  the  surface.  The  moths 
emerge  about  eight  days  later,  so  that  in  midsummer  the  com- 
plete life  cycle  occupies  about  a  month.  In  Texas  there  are 
probably  five  generations  a  year,  and  in  Nebraska  and  Ilhnois 
three  or  four  generations. 

Control. — The  plowing  of  infested  land  in  late  fall  or  winter, 
or  thorough  disking  of  alfalfa  will  be  found  largel}''  to  control  the 
pest.  Where  it  appears  on  cultivated  crops  it  may  be  readily 
destroyed  by  at  once  spraying  or  dusting  with  arsenate  of  lead. 
The  destruction  of  the  weeds  upon  which  it  feeds  is  obviously 
important  in  preventing  the  undue  multiplication  of  the  pest. 

The  Rhubarb  Curculio  * 

Rhubarb  is  but  little  troubled  with  insect  pests,  but  occa- 
sionally  the   stalks   are   found   with   numerous   punctures  from 


Fig.  308. — The  rhubarb  curculio  (Lixus  concavus  Say):  a,  beetle;  b,  egg; 
c,  newly  hatched  larva;  d,  full  grown  larva;  e,  pupa;  /,  back  view  of  last 
abdominal  segment  of  pupa — all  about  twice  natural  size.  (After  Chit- 
tenden, U.  S.  Dept.  Agr.) 

which  the  juice  exudes.     This  has  been  caused  by  the  feeding 

and  oviposition  of  a  large  rusty-brown  snout-beetle,   which  is 

usually  found  on  the  affected  plants.     It  is  about  three-quarters 

*  Lixus   concavus   Say.     Family    CurculionidcB.     See   F.    H.    Chittenden, 
Bulletin  23,  n.  s.,  Division  of  Entomology,  p.  61. 


366 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


inch  long,  and  will  be  readily  recognized  from  Fig.  308  The 
beetles  hibernate  over  winter  and  feed  on  dock,  in  the  stalks  of 
which  the  eggs  are  laid  in  May.  Although  eggs  are  laid  in  rhu- 
barb, they  fail  to  hatch  or  the  young  larvae  die.  The  grubs 
become  full  grown  by  midsummer  and  the  beetles  emerge  in  late 
summer  and  feed  a  little  before  entering  hibernation. 

Control. — As  the  beetles  are  sluggish  and  readily  found,  they 
may  be  easily  destroyed  by  handpicking.  Dock  plants  near  the 
rhubarb  patch  should  be  pulled  and  destroyed  in  early  summer 
after  the  beetles  have  finished  laying  their  eggs. 

The  Celery  Caterpillar  * 

r 

Everyone  who  grows  celery,  parsley  or  carrots  is  famiUar 
with  the  large,  black-striped,  green  caterpillar  which  feeds  on 


Fig.  309. — The  celery  caterpillar  (Papilio  polyxenes  Fab.):  a,  full  grown  larva, 
side  view;  b,  front  view  of  head  showing  extended  osmateria;  c,  male 
butterfly;  d,  egg;  e,  young  larva;  /,  suspended  chrysalis — about  natural 
size  except  d.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

their  foliage,  as  it  is  probably  the  most  common  pest  of  those 
plants  in  all  parts  of  the  country,  ragging  the  foliage  and  attack- 
ing the  blossoms  and  undeveloped  seeds.  It  is  the  larva  of  our 
most  common  black  swallowtail  butterfly,  shown  natural  size  in 
Fig.  309.  The  wings  of  the  male  are  velvety  black  with  bands 
*  Papilio  polyxenes  Fab.     Family  Papilionidoe. 


INSECTS  INJURIOUS  TO  MISCELLANEOUS  CROPS        367 

of  yellow  spots.  On  the  inner  angle  of  the  hind-wing  is  a  well- 
marked  eyespot,  and  the  hind-wing  terminates  in  a  distinct 
"tail."  The  female  is  somewhat  larger,  the  inner  row  of  yellow 
spots  is  wanting,  and  the  hind-wings  are  covered  with  pale-blue 
scales  on  the  posterior  half.  There  is  considerable  variation, 
however,  in  the  color  of  both  sexes. 

Life  History. — In  the  North  the  winter  is  passed  in  the  chrys- 
alis stage  and  the  butterflies  appear  in  May  in  New  England, 
while  in  the  far  South  the  butterflies  hibernate  over  winter  and 
appear  in  March  or  April.  The  eggs  are  laid  on  the  foUage  and 
are  of  a  globular  form,  about  one-twenty-fifth  inch  in  diameter, 
at  first  pale  honey-yellow,  but  later  reddish-brown.  The  eggs 
hatch  in  from  four  to  nine  days.  The  young  larvae  are  quite 
dissimilar  from  the  older  stages,  being  nearly  black  with  a  white 
band  around  the  middle  of  the  body  (Fig.  309e).  The  larvae 
feed  exclusively  on  umbelKferous  plants,  including  besides  those 
mentioned,  caraway,  fennel,  parsnip,  dill,  wild  carrot,  wild  pars- 
nip, and  other  weeds  of  this  family.  The  full-grown  larva  is 
shown,  natural  size,  in  Fig.  309,  a.  It  is  bright  green,  sometimes 
yellowish,  and  marked  with  rings  and  spots  of  velvety  black  as 
illustrated.  Just  back  of  the  pro  thorax  is  a  pair  of  membranous 
yellow  horns  called  osmateria,  which  give  off  a  peculiar  pungent 
odor,  which  is  quite  disagreeable  and  evidently  aids  in  frighten- 
ing away  enemies.  These  osmateria  are  soft,  retractile  organs, 
which  are  drawn  back  between  the  segments  and  are  extruded 
only  when  the  larva  is  disturbed. 

In  the  far  South  the  larva  will  become  grown  in  ten  days, 
but  in  the  North  it  requires  three  to  four  weeks.  The  cater- 
pillar then  attaches  itself  to  some  part  of  the  plant  by  the  anal 
prolegs,  and  fastens  a  strong  loop  of  silk  around  the  thorax,  and 
sheds  its  skin,  leaving  the  chrysaHs  or  pupa  firmly  attached  ;to 
the  leaf  or  stem  as  shown  in  Fig.  309,  /.  The  chrysahs  is  a  dull 
gray  color  marked  with  black  and  brown  and  about  V/i  inches 
long.  In  from  ten  days  to  two  weeks  the  butterfly  emerges 
from  the  chrysahs.  Thus  the  complete  life  cycle  may  be  passed 
in  twenty-two  days  in  the  South  to  eight  weeks  in  the  North. 
In  the  North  there  are  but  two  generations  a  year,  while  in  the 
South  there  are  probably  three  or  four. 

Control. — The  caterpillars  are  so  readily  seen,  and  if  not  seen 
they  soon  reveal  their  presence  by  the  peculiar  odor  when  dis- 


368         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

turbed,  that  they  may  usually  be  picked  off  and  crushed,  and  so 
rarely  become  sufficiently  numerous  to  warrant  other  treatment. 
They  may  be  readily  controlled  by  spraying  or  dusting  with 
arsenicals. 

The  Celery  Looper  * 

This  species  is  very  closely  related  to  the  cabbage  looper 
and  occurs  throughout  the  Northern  States  east  of  the  Rocky 
Mountains.  According  to  Forbes  and  Hart  it  is  more  common 
than  the  cabbage  looper  in  Illinois,  where  it  is  a  serious  pest  of 
celery  and  has  been  reared  on  sugar-beet,  but  elsewhere  it  is 
not  as  common. 

The  moth  has  a  wing  expanse  of  about  two  inches,  the  fore- 
wings  being  purplish  brown  with  darker  shades  of  velvety  brown 


Fig.  310. — The  celery  looper  (Antogragha  simplex  Guen.):  male  moth  and 
larva —  somewhat  enlarged.      (After  Chittenden,  U.  S.  Dept.  Agr  ) 

and  with  a  prominent  silvery  white  discal  spot,  while  the  hind- 
wings  are  yellowish,  strongly  banded  with  dark  fuscous.  The 
caterpillar  or  larva  is  shnilar  to  that  of  the  cabbage  looper,  but 
the  spiracles  are  surrounded  with  black  rings,  while  in  the 
cabbage  looper  these  rings  are  indistinct  or  wanting. 

Forbes  and  Hart  beheve  that  there  are  three  broods  in  a 
year.  "The  caterpillars  of  the  first  generation  of  the  year  hatch 
late  in  May  and  get  their  growth  late  in  June  or  early  in  July. 
The  hfe  of  the  second  generation  extends  from  the  first  part 
of  July  to  the  middle  of  September,  and  the  third  begins  to  issue 
from  the  egg  early  in  October.  This  brood  hibernates  about 
half  grown,  attaining  full  size  during  the  latter  part  of  April." 

Control. — No  accounts  of  experiments  in  control  are  on  record, 
but  doubtless  the  same  measures  as  used  against  the  cabbage 
looper  will  be  found  applicable. 

*  Antographa  simplex  Guen.  Family  Noctuidce.  See  Chittenden,  Bulle- 
tin 33,  Division  of  Entomology,  U.  S.  Dept.  Agr.,  p.  73. 


INSECTS  INJURIOUS  TO  MISCELLANEOUS  CROPS        369 


The  Carrot-beetle  * 

The  Carrot-beetle  is  a  native  species  which  has  been  particu- 
larly injurious  to  carrots  along  the  Atlantic  Coast  from  Long 
Island  through  the  Gulf  States.  The  species  occurs,  however, 
very  generally  throughout  the  country  as  far  north  as  central 
Indiana,  and  on  the  Pacific  coast.  It  has  a  considerable  number 
of  food-plants;  in  Louisiana  and  Mississippi  it  has  injured  the  corn 
crop,  the  beetles  cutting  the  corn  just  above  the  roots;  in  Illinois 
the  beetles  injured  sunflowers 
and  sweet  potatoes;  in  Indiana 
they  attacked  carrots,  celery  and 
and  parsnips;  in  Texas  they 
have  injured  potatoes  and 
shrubs  and  vegetables  of  various 
kinds;  and  in  Nebraska  they 
have  damaged  sugar-beets. 

The  damage  is  done  entirely 
by  the  adult  beetles,  which  arc 
among  the  smaller  of  the  May- 
beetles  or  June-bugs,  measure 
one-half  to  five-eighths  of  an 
inch  long,  and  are  from  reddish- 
brown  to  nearly  black  in  color. 


Fig.  311. — The  carrot-beetle  (Ligyrus 
gibbosus  DeG.)  —  much  enlarged. 
(After  Forbes.) 


The  beetles  gouge  into  the  roots  or  stems  just  below  the  surface 
of  the  soil,  often  ruining  the  root  for  market  without  injuring  the 
top.  The  injury  may  occur  by  hibernated  beetles  in  the  spring 
from  April  to  June  or  by  newly  transformed  individuals  in  late 
summer  or  autumn. 

The  life  history  has  not  been  studied,  but  is  probably  very 
similar  to  that  of  Lachnosterna. 

Control. — No  very  satisfactory  means  of  control  have  been 

tried  in  a  practical  way.     It  is  stated  that  lime  scattered  over 

infested  fields  has  driven  the  beetles  away.     It  is  evident  that 

after  the  crop  is  gathered  infested  fields  should  be  pastured  with 

hogs,  if  possible,   or  plowed  deeply,   and  plowed  again  in  the 

spring.     Evidently  further  study  of  the  habits  of  the  pest  is 

necessary  before  satisfactory  means  of  control  may  be  devised. 

*  lAgyrus  gibbosus  DeG.  Family  Scaraboeidoe.  See  F.  H.  Chittenden, 
Bulletin  33,  n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr.,  p.  32,  and  W.  P.  Hayes,  Journal 
Ec.  Ent.  Vol.  10,  pp.  253-261,  1919. 


370 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Carrot  Rust-fly  * 

The  Carrot  Rust-fly  is  a  European  species,  being  a  serious 
pest  of  carrots  in  England  and  Germany,  which  has  been  known 
in  Canada  since  1885  and  appeared  in  New  York  in  1901  and 
since  then  in  New  Hampshire.  The  larva  or  maggot  which  does 
the  injury  very  much  resembles  the  cheese  maggot  or  skipper  in 
general  appearance,  is  a  rather  dark  brown,  and  a  little  less  than 
one-third  inch  long.  The  parent  fly  is  about  one-sixth  inch 
long  with  a  wing  expanse  of  three-tenths  inch,  and  is  a  dark 


Fig.  312.— -The  carrot  rust-fly  {Psila  rosoe  Fab.):  'b,  male  fly;  o , female flys, 
side  view;  a,  antenna  of  male;  b,  full-grown  larva  from  side;  c,  spiracle 
of  same;  a,  anal  extremity  from  the  end;  e,  puparium;  /,  young  larva; 
g,  anal  segment  from  the  side — eight  times  natural  size  except  a,  c,  d,  g, 
more  enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

blackish-green  color,  sparsely  clothed  with  yellow  hairs,  and  with 

pale  yellow  head  and  legs,  except  the  eyes,  which  are  black. 

"Attack  on  carrots  is  not  difficult  of  recognition.    The  leaves 

of  the  young  plants  early  in  the  spring  turn  reddish,  and  the 

roots  are  found  to  be  blotched  with  rusty  patches,  particularly 

toward  their  tips.     The  roots  when  stored  for  winter,  although 

not  always  manifesting  any  degree  of  injury  on  the  outer  surface, 

may  at  times  be  perforated  in  all  directions  by  dirty  brownish 

burrows,   from  which  the  whitish  or  yellowish  larvae  may  be 

found  sometimes  projecting."     Celery  is  also  attacked,  the  larvse 

*  Psila  rosoe  Fab.     Family  Psilidce.     See  Chittenden,  Bulletin  33,  n.  s. 
Division  of  Entomology,  U.  S.  Dept.  Agr.,  p.  26. 


INSECTS  INJURIOUS  TO  MISCELLANEOUS  CROPS         371 

eating  the  thick  part  of  the  root  when  it  is  half  grown,  stunting 
the  plant  so  as  to  make  it  worthless  for  market.  The  life  history 
of  the  species  does  not  seem  to  have  been  carefully  observed, 
but  from  analogy  is  probably  somewhat  similar  to  that  of  the 
cabbage  root-maggot,  except  that  the  maggots  of  the  carrot 
rust-fly  develop  and  transform  on  carrots  in  storage  if  the  tem- 
perature be  sufficient. 

Control. — Control  measures  as  recommended  for  this  insect 
have  not  proven  of  any  great  benefit  so  we  must  wait  for  addi- 
tional information  before  making  definite  suggestions. 

The  Parsnip  Webworm  * 
The  Parsnip  Webworm  is  quite  a  common  pest  of  the  forming 


Fig.  313. — The  parsnip  webworm  (Depressaria  heracliana  De  G.):  a,  moth, 
b,  c,  larvae;  d,  pupa;  e,  anal  extremity  of  pupa;/,  umbel  of  parsnip  webbed 
together  by  the  larvae — natural  size.     (After  Riley.) 

seed  of  the  parsnip,  but  fortunately  it  seems  to  prefer  wild  carrot 
as  a  breeding  plant.  It  is  an  imported  species,  occurring  in  north- 
ern Europe,  which  was  first  observed  in  this  country  in  1873  and 
since  then  has  become  generally  distributed  over  the  Northern 
States  and  Canada  westward  to  the  Mississippi. 

The  moth  is  a  grayish-buff  or  pale  ochreous  color,  marked  with 
fuscous,  the  wings  expanding  about  three-quarters  of  an  inch. 
The  larva  is  a  pale  yellowish,  greenish  or  bluish-gray,  with  con- 
spicuous black  tubercles,  the  head  and  prothoracic  shield  black, 


*  Depressaria  heracliana  DeG.     Family  (Ecophoridce.     See  C.  V.  Riley, 
"Insect  Life,"  Vol.  I,  p.  94. 


372         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

and  is  about  half  an  inch  long  when  grown.  The  larvae  web  the 
flower-heads  together  until  they  are  contracted  into  masses  of 
web  and  excrement  i  as  shown  in  the  illustration.  "After  the 
larvse  have  consumed  the  flowers  and  unripe  seeds  and  become 
nearly  full  grown,  they  enter  the  hollow  stems  of  the  plant  by 
burrowing  their  way  inside,  generally  at  the  axils  of  the  leaves, 
and  then  feed  upon  the  soft,  white  lining  of  the  interior.  Here, 
inside  the  hollow  stem,  they  change  to  the  pupa  state.  The 
larvae  are  moderately  gregarious.  They  will  sometimes  eat  newly 
sown  parsnips  after  the  older  plants  originally  attacked  have 
been  destroyed,  in  such  cases  eating  the  tender  green  leaves,  while 
of  the  older  plants  they  eat  only  the  flower-heads  and  interior 
lining  of  the  stems."  The  moths  appear  in  late  July  and  early 
August. 

Control. — Thorough  spraying  or  dusting  with  arsenicals  will 
destroy  the  caterpillars,  according  to  Chittenden.  If  the  flowers 
are  destroyed  before  they  are  noticed,  cut  off  and  burn  all  infested 
stems  before  the  moths  emerge  from  the  pupae.  Obviously  it  will 
be  important  to  avoid  planting  parsnips  in  or  near  waste  places 
which  have  grown  up  in  wild  carrot. 

The  Onion  Thrips  * 

The  small  yellowish  "thrips"  which  chafe  the  epidermis  from 
the  green  leaves,  causing  them  to  dry  out,  whiten  and  die,  have 
become  well  known  to  onion  growers  in  practically  all  parts  of 
the  United  States  where  onions  are  raised  extensively.  It  is  a 
European  insect,  occurring  in  Germany  and  Russia,  and  has  also 
been  imported  into  the  Bermudas. 

The  adult  thrips  is  about  one-twenty-fifth  of  an  inch  long,  of 
a  pale  yellow  color,  tinged  with  blackish.  The  general  appear- 
ance, much  enlarged,  is  shown  in  Fig.  314.  The  slender,  elongate 
body  bears  two  pairs  of  narrow,  bristle-like  wings  which  are  of 
no  value  for  flight.  The  fore-wing  contains  two-wing-veins,  and 
the  hind-wing  but  one,  the  posterior  margin  of  both  bearing  a 

*  Thrips  tabaci  Lind.  Order  Thysanoptera.  See  Quaintance,  A.  L., 
Bulletin  46,  Fla.  Agr.  Exp.  Sta.,  "The  Strawberry  Thrips  and  the  Onion 
Thrips."  Full  account  and  Bibliography;  Pergande,  Th.,  "Insect  Life," 
Vol.  VII,  pp.  292-295;  Osborne-Mally,  Bulletin  27,  Iowa  Agr.  Exp.  Sta., 
pp.  137-142;  Sirrine,  Bulletin  83,  N.  Y.  Agr.  Exp.  Sta.,  pp.  680-683,  Farmers' 
Bulletin  1007,  U.  S.  D.  A. 


INSECTS  INJURIOUS  TO  MISCELLANEOUS  CROPS        373 

fringe  of  long  hairs.     When  at  rest  the  wings  he  together  along 
the  back. 

The  thrips  belong  to  a  quite  distinct  order  of  insects,  the 
Thysanoptera  (or  Physopoda),  species  of  which  are  commonly 
found  in  the  flowers  of  the  rose  and  clover.  The  mouth-parts 
are  quite  different  from  those  of  any  other  order  of  insects,  being 
intermediate  between  those  of  biting  and  sucking  insects,  the 
mandibles  being  reduced  to  bristle-like  structures.  Their  man- 
ner of  feeding  does  not  seem  to  be  clearly  understood,  though 


Fig.  314. — ^The  onion  thrips  (Thrips  tabaci  Lind.) — ^very  greatly  enlarged. 
(Photo  by  Quaintance.) 

Professor  Quaintance  states  that  the  onion  thrips  frequently 
rasps  off  and  swallows  pieces  of  leaf  tissue.  However,  they  are 
able  to  destroy  the  surface  tissue  of  the  leaf  so  that  it  wilts, 
and  fields  badly  affected  become  blighted  and  white. . 

This  species  has  quite  a  list  of  food-plants,  cabbage  and  cauU- 
fiower  often  being  considerably  injured.  Among  others  may  be 
mentioned  turnip,  kale,  sweet  clover,  squash,  cucumber,  melon, 
parsley,  tomato,  and  several  common  garden  flowers  and  weeds. 

Life  History. — The  eggs  are  slightly  less  than  .01  of  an  inch 
long — too  small  to  be  visible  to  the  unaided  eye — elongate,  and 
curved  somewhat  kidney-shaped.  They  are  laid  singly  just 
beneath  the  surface  of  the  leaf  and  hatch  in  about  four  days. 


374         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  young  nymphs  resemble  the  adults  in  shape,  but  are  at 
first  almost  transparent  in  color  and  then  a  greenish-yellow. 
They  are  frequently  found  feeding  in  small  groups.  Both  the 
young  and  adults  have  a  pair  of  sharp  spines  at  the  tip  of  the 
abdomen  which  they  use  to  drive  away  enemies  by  striking  them 
quickly  right  and  left.  Two  or  three  days  after  birth  the  skin  is 
shed  and  another  molt  occurs  five  or  six  days  later.  With  the 
third  stage  the  wing-pads  appear.  This  stage  lasts  four  days, 
and  during  it  the  insects  take  no  food  and  remain  almost  quiet, 
moving  with  difficulty.  On  onions  the  nymphs  have  been  found 
mostly  on  the  bulbs  in  the  loose  soil.  With  the  next  molt,  the 
insect  becomes  mature  and  winged.  Thus,  the  total  fife  cycle 
as  observed  by  Professor  Quaintance  in  Florida  is  about  sixteen 
days.  In  Russia  Dr.  Lindeman  found  that  a  generation  required 
forty-seven  days.  "In  Florida  there  are  probably  no  distinct 
broods,  as  all  stages  may  be  found  at  the  same  time.  Allowing 
for  the  fife  cycle  at  sixteen  days,  a  large  number  of  broods  could 
occur  during  the  year,  but  unfavorable  conditions  keep  them 
reduced,  except  during  the  spring  and  perhaps  early  summer  (the 
worst  injury  occurring  in  May  and  June),  so  that  it  will  prob- 
ably not  happen  that  they  will  develop  throughout  a  year  accord- 
ing to  their  capabilities." 

Control. — The  best  methods  of  control,  according  to  Dr. 
Chittenden,  include  clean  farming  and  crop  rotation  as  pre- 
ventive measures  and  spraying  with  nicotine  sulphate  as  a  direct 
method  of  kilhng  the  thrips.  High  pressure  should  be  used  in 
spraying  and  the  spray  should  be  directed  downward  so  that  it 
will  be  forced  into  the  crevices  between  the  leaves  or  stems,  in 
which  the  thrips  conceal  themselves. 

The  Imported  Onion-maggot  * 

The  common  white  maggot  which  bores  into  the  roots  and 

bulbs,  causing  them  to  wilt  and  decay,  is  probably  the  most 

important  insect  pest  of  the  onion.     The  present  species  is  by  far 

the  most  commonly  injurious  and  is  termed  "  imported"  because 

it  was  early  known  as  a  pest  in  Europe  and  was  imported  into 

this  country  probably  in  colonial  times. 

*  Pegomyia  ceparum  Bouche.  Famrly  Anthomyiidce.     See  same  references 
as  for  cabbage-maggot. 


Fig.  315. — ^The  imported  onion-maggot  (Pegomyia  ceparum  Bouch6):  a, 
adult;  b,  maggot;  c,  puparium;  d,  anal  segment  of  maggot  showing 
spiracles;  e,  head  with  mouth-parts — all  very  much  enlarged;  /  and  g 
show  injury  to  young  onions.     (After  J.  B.  Smith.) 

375 


376         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

These  maggots  are  the  offspring  of  small  flies,  somewhat 
resembling  small  houseflies  and  very  similar  to  those  of  the 
cabbage  root-maggot.*  The  wings  expand  about  three-eighths 
of  an  inch  and  the  body  is  half  that  long.  The  male  is  gray  with 
black  bristles  and  hairs,  the  face  is  white  with  black  hairs,  there 
are  three  black  lines  between  the  wings,  and  the  abdomen  bears 
a  row  of  black  spots  along  the  middle.  The  female  is  a  little 
larger,  inclined  to  dark  yellowish,  and  with  a  yellowish  face. 

Life  History. — The  flies  appear  in  the  spring  by  the  time 
young  onions  are  up  and  the  eggs  are  deposited  in  the  sheath 
and  in  the  axils  of  the  leaves,  from  two  to  six  being  placed  upon 
a  plant.  The  eggs  are  just  perceptible  to  the  eye,  white,  oval, 
and  about  one-twenty-fifth  of  an  inch  long.  The  young  maggot 
works  its  way  down  from  the  sheath  to  the  root,  upon  which  it 
feeds  until  it  is  consumed,  only  the  outer  skin  remaining,  and 
often  cuts  off  the  plant  completely.  Another  plant  is  then 
attacked  and  often  several  young  plants  are  consumed  before 
the  maggot  is  full  grown.  Later  in  the  season  the  maggots  bore 
into  the  bulbs,  a  number  of  maggots  usually  being  found  in  a 
single  bulb  and  their  presence  being  indicated  by  a  slimy  mass 
of  soil  at  the  entrace  of  the  cavity.  If  such  bulbs  are  not  killed 
outright,  they  usually  rot  in  storage.  The  first  presence  of  the 
pest  is  indicated  by  the  wilting  of  the  young  plants,  and  by  the 
central  leaves  of  the  older  plants  yellowing  and  dying. 

The  maggots  become  full  grown  about  two  weeks  after  hatch- 
ing and  are  then  about  three-eighths  of  an  inch  long.  They  are 
dull  white,  with  the  jaws  appearing  beneath  the  skin  as  a  short 
black  stripe  at  the  pointed  end  of  the  body.  The  posterior  end 
of  the  body  is  obtuse  and  is  cut  off  obliquely,  the  margin  of  the 
last  segment  bearing  a  number  of  tubercles  by  which  this  species 
may  be  distinguished  from  the  cabbage-root  maggot.  (See 
Slingerland,  I.e.) 

The  outer  skin  of  the  maggot  now  becomes  hardened  and 

within  it  the  insect  transforms  to  the  pupa,  which  remains  in  the 

soil  at  the  base  of  the  plant  for  about  two  weeks,  when  the  adult 

fly  emerges.     Two  or  three  generations  probably  occur  in  the 

Northern  States.     Professor  R.  H.  Pettit  states  that  some  of  the 

*  See  Slingerland,  Bulletin  78,  Cornell  Agr.  Exp.  Sta.,  p.  495,  for  characters 
distinguishing  these  two  species. 


INSECTS  INJURIOUS  TO  MISCELLANEOUS  CROPS        377 


flies  hibernate  while  many  of  the  pupae  remain  in  the  soil  over 
winter  and  the  flies  issue  from  them  in  the  spring.  This  com- 
plicates remedial  measures. 

Control. — Liberal  apphcations  of  commercial  fertilizers  such 
as  nitrate  of  soda,  which  will  assist  to  rapid  growth,  are  of  great 
value  in  overcoming  injury  by  all  root-feeding  pests.  Thorough 
culture  is  of  value.  Rotation  of  the  onion  plot  to  a  point  far 
distant  from  that  of  the  previous  year,  the  cleaning  up  of  old 
beds,  and  plowing  them  deeply  in  the  fall,  will  aid  in  the  control. 
Pull  up  and  destroy  the  young  plants  affected  as  soon  as  noticed, 
being  careful  to  dig  up  the  maggots  with  the  roots.     The  appli- 


£U 


Fig.  316. — The  barred-winged  onion-maggot  {Chcrtopsis  cenea  Wied.):  a, 
larva,  with  spiracular  opening  highly  magnified  at  left;  b,  puparium; 
c,  adult  fly — all  enlarged.     (After  Riley  and  Howard,  U.  S.  Dept.  Agr.) 

cation  of  carbolic  emulsion  as  for  the  cabbage-root  maggot  has 
been  advocated  and  will  doubtless  lessen  the  injury  by  repelling 
the  adult  flies. 

A  more  recent  method  of  control  is  based  on  the  fact  that 
the  flies  are  on  the  wing  and  feeding  for  several  days  before  they 
lay  their  eggs  and  that  they  may  be  attracted  to  sweet  sub- 
stances. A  poisoned  syrup,  sprinkled  about  the  field  and  on 
weeds  nearby,  will  attract  the  flies  and  kill  large  numbers  before 
they  lay  their  eggs.     The  syrup  is  poisoned  as  follows: 

One  pint  of  syrup  is  mixed  with  a  gallon  of  water  and  to  this 
is  added  one-fifth  ounce  of  sodium  arsenite  dissolved  in  a  small 
quantity  of  hot  water.  This  is  sprinkled  where  it  will  do  the 
most  good  at  intervals  of  about  a  week.* 

*  See  Severin  and  Severin,  Journal  Econ.  Ent.,  Vol.  8,  pp.  342-350,  1915, 
and  Howard,  ibid.  Vol.  II,  pp.  82-85,  1918! 


378         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Barred-winged  Onion-maggot  * 

The  adult  flies  of  this  species  may  frequently  be  found  upon 
corn  and  are  readily  recognized  by  the  banded  wings.  They  are 
similar  in  size  to  the  last  species,  but  the  back  is  metallic  blue- 
green  except  the  head,  which  is  mostly  hoary,  with  brownish- 
black  eyes.  The  maggots  have  been  recorded  as  injurious  to 
corn  and  sugarcane  and  have  been  recently  noted  in  Michigan 
associated  with  the  common  onion-maggot,  destroying  onions,  f 
The  maggots  are  similar  to  the  onion-maggot  but  the  posterior 
end  is  more  rounded  and  may  be  distinguished  from  the  illus- 
trations.  The  winter  is  passed  in  the  puparium  as  far  as  observed. 

Remedies. — In  addition  to  the  measures  advocated  for  the  last 
species,  the  destruction  of  the  affected  onions  and  the  thorough 
plowing  of  affected  land  in  the  fall  is  of  prime  importance.  Stored 
onions  which  prove  infested  may  be  fumigated  with  carbon  bisul- 
fide to  destroy  the  maggots  and  puparia  and  prevent  the  emerg- 
ence of  the  adults. 

The  Asparagus-beetle  % 

This  is  a  well-known  pest  of  asparagus  in  Europe  and  was 
first  observed  in  Queens  County,  New  York,  in  1862,  where  it 
threatened  to  destroy  the  asparagus,  one  of  the  most  valued 
crops  of  the  Long  Island  truckers.  Since  then  it  has  gradually 
spread  northward  to  southern  New  Hampshire,  south  to  North 
Carohna,  and  west  to  Illinois  and  Wisconsin,  and  has  been  found 
at  two  points  in  California.  There  seems  no  reason  why  it  should 
not  spread  to  wherever  asparagus  is  grown,  at  least  in  the  North- 
ern States. 

The  beetle  is  a  handsome  little  creature  about  one-quarter 
inch  long,  blue-black  in  color,  with  red  thorax,  and  dark  blue 
wing-covers,  marked  with  lemon-yellow  and  with  reddish  bor- 
ders. The  markings  of  the  wing-covers  are  quite  variable,  the 
light  color  sometimes  forming  submarginal  spots,  while  in  other 
specimens  it  becomes  so  diffused  as  to  form  the  principal  color 
of  the  wing-covers. 

*  Chcetopsis  aenea  Wied.     Family  Anthomyidce. 

t  See  Pettit,  Bulletin  200,  Mich.  Agr.  Exp.  Sta.,  p.  206. 

j  Crioceris  asparagi  Linn.  Family  ChrT/somelidce.  See  F.  H.  Chittenden, 
Yearbook,  U.  S.  Dept.  Agr.,  1896,  p.  341;  Bulletin  66,  Bureau  of  Ent.,  pp. 
6,  93,  and  Farmers'  Bulletin  837. 


INSECTS  INJURIOUS  TO  MISCELLANEOUS  CROPS        379 


Both  adults  and  larva?  feed  upon  the  tender  asparagus  shoots 
in  the  spring  and  later  attack  the  fruiting  plants.  Their  attacks 
render  the  shoots  unfit  for  market  and  in  many  cases  their  injury 
has  been  so  severe  as  to  make  it  extremely  difficult  to  establish 
new  beds. 

Life  History. — The  beetles  hibernate  over  winter  under  what- 
ever rubbish  or  shelter  may  be  available  near  the  asparagus 
patch.  About  the  season  that  cutting  asparagus  for  market 
commences  they  appear  and  lay  the  eggs  for  the  first  new  brood 


Fig.  317. — The  asparagus-beetle  (Crioceris  asparagi  Linn.):  eggs,  larva,  and 
beetle — all  much  enlarged.     (Photos  by  W.  E.  Britton.) 

The  egg  is  dark  brown,  oval,  nearly  one-sixteenth  of  an  inch 
long  and  is  laid  on  end.  The  eggs  are  deposited  upon  the  stems 
or  foliage,  usually  two  to  seven  or  more  in  a  row.  They  hatch 
in  from  three  to  eight  days.  The  young  larvse  at  once  com- 
mence to  attack  the  tender  shoots,  and  later  in  the  season  feed 
upon  the  foliage.  They  become  full  grown  in  from  ten  days 
to  two  weeks.  The  full  grown  larva,  as  shown  in  the  illustra- 
tion, is  about  one-third  of  an  inch  long,  soft  and  fleshy,  much 
wrinkled,  and  of  a  dark  gray  or  olive  color,  with  black  head 
and  legs.  The  mature  larva  drops  to  the  ground  and  just  be- 
neath the  surface  forms  a  little  rounded  earth-covered  cocoon 
within  which  it  changes  to  the  pupa,   from  which  the  beetle 


380  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

emerges  in  about  a  week.  Thus  the  complete  Hfe  cycle  may- 
be passed  in  a  minimum  of  three  weeks  at  Washington,  D.  C, 
where  there  are  possibly  four  generations  in  a  year,  while  farther 
north,  six  or  seven  weeks  may  be  required  for  the  life  cycle,  and 
there  are  probably  only  two  generations. 

The  asparagus-beetles  are  held  in  check  by  several  natural 
agencies.  Several  species  of  ladybird-beetles  feed  upon  the  eggs, 
while  numerous  soldier-bugs  attack  the  larvae  which  they  impale 
on  their  stout  beaks.  The  adult  beetles  are  often  killed  by  low 
temperature  in  the  winter,  which  doubtless  limits  their  northern 
spread,  while  the  eggs  and  larvse  are  sometimes  killed  by  the 
intense  heat  of  summer,  which  will  also  probably  limit  the  south- 
ern spread  of  the  species. 

Control. — One  of  the  best  means  of  control  is  to  keep  all 
shoots  cut  down  in  the  spring  so  as  to  force  the  beetles  to  lay 
their  eggs  on  the  young  shoots,  which  are  cut  for  market  every 
few  days  before  the  eggs  have  hatched,  and  hence  no  larvae  are 
allowed  to  hatch. 

Another  method  which  has  proven  effective  is  to  cut  down 
all  the  seed  stems  but  a  few  rows  here  and  there,  so  that  the 
beetles  will  concentrate  upon  them,  and  then  poison  these  thor- 
oughly with  arsenicals,  or  they  may  be  cut  down  and  burned 
and  other  rows  allowed  to  grow  as  traps. 

Air-slaked  lime  dusted  on  the  plants  in  the  morning  while 
the  dew  is  on  will  destroy  the  soft-bodied  larvse  very  effectively. 
Another  way  to  destroy  the  larvae  in  hot  weather  is  simply  to 
brush  them  from  the  plants  so  that  they  will  drop  on  the  hot 
soil.  As  they  crawl  but  slowly  few  will  regain  the  plants,  par- 
ticularly if  the  brushing  be  followed  with  a  cultivator. 

Probably  the  most  effective  means  of  controlling  this  pest, 
which  was  formerly  a  very  difficult  one  to  combat,  is  spraying 
with  arsenate  of  lead.  Use  3  pounds  to  50  gallons,  to  which  3 
pounds  of  resin  soap  should  be  added  to  render  it  more  adhesive, 
although  good  results  have  been  secured  without  the  sticker. 
Such  spraying  should  be  given  as  soon  as  cutting  is  over  and  should 
be  repeated  once  or  twice  at  intervals  of  ten  days.  Where  the 
young  shoots  are  kept  closely  cut  and  the  bed  is  then  sprayed, 
there  should  be  no  trouble  to  control  the  pest,  and  young  beds 
should  be  kept  thoroughly  sprayed  with  arsenate  of  lead  from 
the  time  the  beetles  appear  until  danger  from  injury  is  over. 


INSECTS  INJURIOUS  TO  MISCELLANEOUS  CROPS        381 


The  Twelve-spotted  Asparagus-beetle  * 

The  Twelve-spotted  Asparagus  Beetle  is  also  of  European 
origin,  having  been  first  introduced  into  this  country  near  Balti- 
more, Md.,  in  1881.  Since  then  it  has  become  almost  as  widely- 
distributed  as  the  previous  species. 

The  beetles  may  be  distinguished  from  the  last  species  by 
the  broader  wing-covers,  each  of  which  is  orange-red,  marked 
with  six  black  spots.  The  chief  injury  by  this  species  is  by  the 
beetles  which  emerge  from  hibernation  feeding  on  the  young 
shoots.  Later  generations  attack  the  foliage,  but  the  larvae 
seem  to  prefer  to  feed  upon  the  ripening  berries.  The  larva  is 
of  the  same  general 
appearance  as  that 
of  the  preceding  spe- 
cies, but  may  be  dis- 
tinguished by  its 
orange  color.  The 
eggs  are  laid  singly, 
and  are  attached  on 
the  sides  instead  of 
on  end.  They  are 
deposited  mostly  on       t-  i  ^-^  —  i 

old    plants    toward  Fiq.  318.— The  twelve-spotted  asparagus-beetle  {Cri- 
the    ends    of    the      ocens  12-puncta(a  Linn.):  a,   beetle;   b,   larva;   c, 
u      +  U'  V.     K  second  abdominal  segment  of  larva;  d,  same  of 

shoots  which  bear  c,  asparagi — a,  b,  enlarged;  c,  d,  more  enlarged, 
ripening     berries      (After  Chittenden,  U.  S.  Dept.  Agr.) 

lower  down.  Soon  after  a  larva  hatches  it  finds  its  way  to  a  berry 
and  feeds  upon  its  ripening  pulp,  from  which  it  migrates  to  an- 
other, feeding  upon  several,  perhaps,  before  full  growth  is  obtained, 
when  it  drops  to  the  ground  and  pupates  like  the  last  species. 
The  Kfe  cycle  is  essentially  the  same  and  there  are  probably  the 
same  number  of  generations. 

Control. — The  remedies  advocated  for  the  previous  species 
will  be  found  satisfactory  except  those  which  are  directed  against 
the  larvae,  as  the  habit  of  the  larva  of  concealing  itself  in  the 
berry  would  make  the  application  of  insecticides  to  the  seed- 
stalks  of  little  use. 

*  Crioceris  12-punctata  Linn.  See  F.  H.  Chittend3n,  I.e.,  and  D.  E.  Fink, 
Cornell  Univ.  Expt.  Sta.,  Bulletin  331. 


382         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Asparagus  Miner  * 

Occasionally  injury  by  the  small  white  maggots  of  a  fly  have 
been  observed  in  the  asparagus  beds  of  Long  Island,  California, 
Pennsylvania,  Massachusetts  and  District  of  Columbia,  but  the 
damage  seems  rarely  to  be  very  serious.  The  adult  is  a  small 
black  fly  about  one-sixth  of  an  inch  long  and  is  usually  found 
on  the  flowers  of  the  asparagus,  and  occurs  from  New  England 
to  Tennessee.  These  flies  emerge  early  in  June.  The  exact  manner 
of  egg-laying  has  not  been  observed,  but  the  young  maggots  are 


Fig.  319. — The  asparagus  miner  (Agromyza  simplex  Loew) :  at  left,  side  view 
of  fiy;  a,  larva;  b,  thoracic  spiracles;  c,  anal  spiracles;  d,  puparium  from 
side;  e,  same  from  above;  /,  section  of  asparagus  stalk  showing  injury 
and  location  of  puparia  on  detached  section — a,  e,  much  enlarged;  /, 
slightly  reduced.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

found  mining  just  beneath  the  surface  of  the  stalks,  especially 
young  stalks.  The  maggots  are  about  one-fifth  of  an  inch  long,  pure 
white,  except  the  black  rasping  hooks  which  project  from  the 
head.  When  full  grown  the  maggots  change  to  puparia  beneath 
the  epidermis.  The  next  brood  of  adult  flies  emerge  early  in 
August.  A  second  brood  of  maggots  seems  to  occur  and  the 
puparia  of  the  second  brood  pass  the  winter,  and  from  them 
come  the  flies  early  the  next  summer. 

Injury  from  the  mining  of  the  maggots  has  been  most  serious 
on  seedhng  and  newly  set  beds,  though  it  may  occur  on  cutting 

*  Agromyza  simplex  Loew.  Family  Agromyzidce.  See  Sirrine,  Bulletin 
189,  N.  Y.  Agr.  Exp.  Sta.;  Chittenden,  Bulletin  66,  Part  I,  Bureau  of  Ento- 
mology, pp.  1  and  5,  Fig.  2,  and  D.  E.  Fink,  Bulletin  331,  Cornell  Univ.  Agr. 
Exp.  Station. 


INSECTS  INJURIOUS  TO  MISCELLANEOUS  CROPS        383 


beds,   being  apparent  by  the  plants  turning  yellow  and  dying 
much  earher  than  they  naturally  do. 

Pulling  the  old  stalks  and  burning  them  in  late  summer  seems 
to  be  the  best  means  for  controlling  the  pest,  from  our  present 
knowledge  of  it,  which,  however,  is  still  rather  meager.  Dr. 
Chittenden  has  suggested  that  letting  a  few  stalks  grow  as  a 
trap-crop  to  which  the  flies  might  be  lured,  and  then  destroying 
these  stalks,  might  protect  the  cutting  beds. 

D.  E.  Fink  (I.e.)  recommends  the  addition  of  syrup  to  the 
arsenical  applied  for  the  beetles  so  that  it 
will  act  as  a  poisoned  bait  for  the  flies.     In 
addition  to  this  he  suggests  pulling  the  in- 
fested stalks  in  late  fall  and  early  spring  and  if dC^ml   I 
destroying  them. 

The  Sweet-potato  Flea-beetle  * 

As  soon  as  the  sweet-potato  plants  are 
set  out  they  are  often  attacked  by  hordes  of 
hungry  little  brownish  flea-beetles.  Small 
channels  are  eaten  out  of  both  surfaces  of 
the  leaf  in  a  very  characteristic  manner, 
quite  different  from  the  work  of  other  flea- 
beetles  (Fig.  320),  and  often  the  whole  sur- 
face is  seared  but  never  punctured.  As  a 
result  many  of  the  leaves  of  the  seedling  are 
killed  outright,  turn  brown,  and  decay,  while 
new  leaves  put  out  from  below,  thus  check- 
ing the  growth.  These  attacks  have  been 
found  to  be  worst  on  low  land  and  that  pre- 
viously in  sweet  potatoes,  and  are  always 
first  noticed  near  fence  rows  or  woodland 
where  the  beetles  have  hibernated.  The 
beetle  is  bronzed  or  brassy-brown  about 
one-sixteenth  inch  long,  thick  set,  and  the 
wing-covers  when  seen  under  a  lens  are 
deeply  striated. 


Fig.  320.— The  sweet- 
potato  flea-beetle 
(Ch(E(oc}iema  confinis 
Lee.) :  adult  and  larva 
— much  enlarged. 
(After  J.  B.  Smith.) 


*  Choeiocnema  confinis  Leo.     Family  Chrysomelidoe.     See  Sanderson,   Bul- 
letin 59,  Md.  Agr.  Exp.  Sta.;  J.  B.  Smith,  Bulletin  229,  N.  J.  Agr.  Exp.  Sta, 


384  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Life  History. — The  beetles  hibernate  over  winter  in  rubbish, 
under  logs,  leaves  or  other  vegetation^  and  emerge  early  in  May. 
They  mate  as  soon  as  they  have  fed  a  little,  and  disappear  by 
the  middle  of  June  in  New  Jersey.  But  little  is  known  of  the 
early  stages  of  the  insect  and  they  have  never  been  found  on 
sweet-potato  plants.  The  larvae  have  been  found,  however, 
feeding  on  the  roots  of  bindweed.  The  larva  (Fig.  320)  is  a 
slender,  white  grub,  about  one-eighth  inch  long,  and  feeds  exter- 
nally upon  the  smaller  roots.  The  beetles  appear  again  in  August, 
but  do  not  as  a  rule  feed  on  sweet  potatoes,  preferring  bindweeds 
and  wild  morning-glories,  from  which  they  disappear  in  late 
September. 

Control. — By  dipping  the  plants  in  arsenate  of  lead.  1  pound 
to  10  gallons  of  water,  as  they  are  being  set,  they  will  be  pro- 
tected and  any  beetles  feeding  on  them  will  be  killed.  The 
plants  should  be  allowed  to  dry  slightly  before  being  set.  Dip- 
ping the  plants  is  much  better  than  spraying  them  later,  as  it 
is  practically  impossible  to  completely  cover  the  plant  by  spray- 
ing, as  may  be  done  in  dipping,  which  is  much  quicker  and  less 
expensive.  Late-planted  sweet  potatoes  are  much  less  seriously 
injured,  as  the  beetles  will  seek  out  their  wild  food-plants  and 
become  established  upon  them,  so  that  late  planting  may  be 
resorted  to  when  necessary  or  more  convenient.  Well  grown, 
stocky  plants  will  better  withstand  injury,  and  liberal  fertiliza- 
tion will  enable  them  to  make  a  quick  growth  even  if  slightly 
checked. 

Tortoise-beetles  or  Gold-bugs  * 

Of  all  the  insects  affecting  the  sweet  potato,  the  brilliant 
little  golden  beetles  which  form  one  tribe  {Cassidce)  of  the  large 
family  of  leaf-beetles,  are  the  most  common  and  are  quite  peculiar 
to  it.  They  are  beautiful  insects,  some  of  the  species  appearing 
like  drops  of  molten  gold,  which  has  given  them  the  name  of 
"gold-bugs,"  while  the  broad  expansion  of  the  thorax  and  wing- 
covers  gives  them  a  fancied  resemblance  to  a  tortoise;  hence  the 
name  "tortoise-beetles."  The  species  affecting  the  sweet  potato 
are  classed  in  three  different  genera,  but  are  sufficiently  alike  in 
their  general  habits  and  Hfe  history  to  be  treated  together. 

*  Family  Chrysomelidoe. 


INSECTS  INJURIOUS  TO  MISCELLANEOUS  CROPS       385 


Life  History. — The  beetles  hibernate  over  winter  and  in  the 
spring  before  the  sweet-potato  plants  are  set  they  feed  on  their 
native  food-plant,  the  morning  glory.  As  soon  as  the  plants  are 
set  out,  the  beetles  commence  to  eat  large  round  holes  in  the 
leaves,  and  so  riddle  them  that  many  often  must  be  replanted. 
The  worst  damage,  however,  is  done  to  the  set  on  which  the 
eggs  are  laid.  Rarely  are  the  new  shoots  seriously  eaten  or  are 
eggs  laid  upon  them.  The  larvae  hatch  during  the  first  half  of 
June  in  Maryland,  and  require  slightly  over  two  weeks  to  become 


Fig.  321. — Above — The  golden  tortoise-beetle  {Coptocydahicolor'Fab.):  a,  h, 
larvae;  c,  pupa;  d,  beetle;  egg  at  right — all  enlarged.  (After  Riley.) — Below 
The  two-striped  sweet-potato  beetle  (Cassida  hivittata  Say):  1, larvae  on  leaf; 
2,  larva;  3,  pupa;  4,  beetle — all  enlarged.     (After  Riley.) 

full  grown.  Though  the  larvee  do  considerable  damage  by  eating 
the  foKage,  it  is  not  nearly  as  serious  as  that  done  by  the  beetles. 
The  larvae  are  almost  as  disagreeable  as  the  adult  beetles  are 
attractive,  but  are  nevertheless  very  interesting  creatures.  Each 
of  them  is  provided  with  a  tail-like  fork  at  the  end  of  the  body 
which  is  almost  as  long  as  the  body,  and  in  those  species  in  which 
it  is  depressed,  entirely  conceals  the  insect.  Upon  this  fork  is 
heaped  the  excrement  and  cast  skins  of  the  larva,  and  when 
covered  by  this  "umbrella"  it  is  with  great  difficulty  that  the 
larva  is  distinguished  from  a  bit  of  mud  or  a  bird-dropping. 
The  manner  in  which  this  fork  increases  with  the  size  of  the 


386         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

larva  is  rather  interesting.  At  each  molt,  the  fseci-fork  of  the 
last  stage  is  held  upon  the  new  fseci-fork,  and  in  this  way  those 
of  the  different  stages  are  telescoped,  the  one  inside  the  other, 
and  the  stage  of  growth  of  the  larva  may  be  readily  determined 
by  the  number  of  cast  skins  held  on  the  fork.  From  the  like- 
ness of  this  burden  to  a  pack,  the  larvae  are  often  known  as 
"peddlers."  In  order  more  firmly  to  bind  the  excrement  and 
cast  skins  to  the  fork,  the  larvae  fasten  them  together  by  a  fine 
network  of  silken  threads,  which  are  attached  to  the  spines  at 
the  sides  of  the  body.  When  fully  grown  the  larva  fastens  itself 
to  a  leaf,  its  skin  splits  open  along  the  back,  and  from  it  comes 
the  pupa,  which  is  held  to  the  leaf  by  its  caudal  fork,  which  is 
securely  encased  in  the  faeci-fork  of  the  larval  skin.  About  a 
week  later  the  adult  beetle  emerges,  eats  for  a  few  days  and  then 
disappears  from  the  sweet-potato  patch  until  the  following  spring, 
doubtless  feeding  on  morning  glory  until  it  enters  hibernation. 

Control. — From  the  similarity  of  their  life  history  and  habits 
all  of  these  species  may  be  treated  at  once.  As  the  beetles  do  the 
most  injury  just  after  the  plants  are  set,  they  should  be  dipped 
in  arsenate  of  lead  when  setting,  as  advised  for  the  flea-beetle. 
If  this  has  not  been  done  or  if  the  beetles  are  injurious  in  the 
forcing  bed,  the  plants  should  be  thoroughly  sprayed  with  arse- 
nate of  lead,  3  pounds. per  barrel  or  Paris  green,  I  pound  per 
barrel  with  |  pound  of  freshly  slaked  hme. 

The  Sweet-potato  Root-borer  * 

Since  1890  sweet  potatoes  have  been  seriously  injured  in  parts 

of  Texas  and  Louisiana  by  a  small  white  grub  which  bores  into 

the  stems  and  tubers  both  in  the  field  and  in  storage,  but  strangely 

it  has  not  spread  elsewhere  in  this  country.     In  Texas  the  worst 

injury  has  been  in  Calhoun  and  neighboring  counties  along  the 

Gulf  Coast  where  extensive  growing  of  sweet  potatoes  has  been 

abandoned  on  account  of  the  pest.     During  recent  years  it  has 

spread  to  central  Texas  and  there  seems  to  be  no  reason  why  it 

should  not  spread  over  the  Gulf  States.     It  is  a  cosmopolitan 

insect  being  reported  from  China,  India,  Madagascar,  Australia 

and  Cuba.     It  was  first  noticed  in  the  vicinity  of  New  Orleans 

*  Cylas  formicarius  Oliv.  Family  Curculionidce.  See  Farmers'  Bulletin 
1020,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  MISCELLANEOUS  CROPS        387 


in  1875  and  has  since  spread  northward  along  the  Mississippi.* 
In  1879  it  was  reported  from  Florida  and  was  studied  by  Pro- 
fessor J.  H.  Comstock.f 

The  adult  beetle  is  a  rather  slender  insect,  about  one-quarter 
inch  long,  of  a  bluish-black  color,  with  a  reddish-brown  pro- 
thorax,  and  has  received  its  specific  name,  formicarius,  from  its 
fancied  resemblance  to  an  ant. 

Life  History. — The  yellowish-white,  oval  eggs  are  deposited  in 
small  cavities  eaten  out  by  the  mother  beetle  either  at  the  base 
of  the  vine  or  at  the  stem  end  of  the  tuberous  root,  or  in  the 


Fig.  322. — Present  known  distribution  of  the  sweet-potato  weevil  in  the 
southern  United  States.     (Farmers'  Bulletin  1020). 

tubers  in  storage.  The  small  grubs  commence  to  burrow  in  the 
vine,  sometimes  maturing  in  the  vine  before  any  tubers  have 
developed,  but  usually  they  descend  to  the  tubers,  which  in  the 
course  of  the  season,  and  with  the  aid  of  the  beetles,  they  thor- 
oughly riddle.  The  full-grown  larva  is  about  one-quarter  inch 
long,  whitish  with  light  brown  head,  the  segments  are  strongly 
constricted,  and  the  legs  are  wanting,  being  represented  by  mere 
tubercles.  The  grub  forms  a  small  cavity  at  the  end  of  the 
burrow  and  transforms  to  the  pupa.  In  this  stage  it  remains 
from  one  to  two  weeks,  when  the  adult  beetle  emerges  and  after 
a  few  days  commences  to  lay  eggs  for  another  generation.  The 
whole  Hfe  cycle  requires  from  thirty  to  forty  days,  so  that  there 
may  be  several  generations  in  a  year.  Professor  Comstock  having 

♦  Bulletin  28,  La.  Agr.  Exp.  Sta.,  p.  999. 

t  See  Report  U.  S.  Comm.  Agr.,  for  1879,  p.  249. 


388         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


observed  three  generations.  In  central  Texas  the  beetles  hiber- 
nate over  winter,  but  in  south  Texas  they  continue  to  breed  in 
the  bins  during  the  winter. 

Control. — Dr.  F.  H.  Chittenden  (I.e.)  recommends  the  follow- 
ing methods  for  control  in  addition  to  the  quarantine  measures 
which  have  been  established  by  various  states  to  prevent  the 
spread  of  the  beetle  in  shipments  of  infested  potatoes.  Rotation 
of  crops,  especially  valuable  since  the  weevil  does  not  breed  in 
crops  other  than  the  sweet  potato  and  does  not  breed  in  any 
other  plants  except  a  few  closely  related  weeds,  is  the  first  recora- 


FiG.  323. — The  sweet-potato  root-borer  (Cylas  formicarius) :  extreme  left 
hand  figure,  adult  beetle,  with  enlarged  antenna?  at  right;  figure  at  left 
center,  pupa;  at  right  center,  larva;  at  extreme  right,  portion  of  sweet- 
potato  tuber  channeled  by  borer — all  figures  except  the  last  considerably 
enlarged;  natural  sizes  indicated  by  hair  lines.  (After  Farmers'  Bulletin, 
No.  26,  U.  S.  Dept.  Agr.) 

mendation.  Clean  culture,  including  the  destruction  of  all  refuse 
from  infested  fields,  and  the  burning  or  feeding  to  hogs  of  all 
damaged  potatoes.  Removal  of  the  seed  beds  as  far  as  possible 
from  the  field  where  the  potatoes  are  to  be  grown  has  also  proven 
of  great  value  in  reducing  the  amount  of  damage.  Dipping  the 
plants,  before  setting,  in  a  solution  of  lead  arsenate  and  later, 
spraying  with  an  arsenical,  zinc  arsenite  being  suggested  as 
having  given  success,  to  kill  the  early  appearing  beetles,  are 
also  recommended.  Prompt  harvesting,  as  soon  as  the  potatoes 
are  ready,  and  the  separation  of  damaged  potatoes  is  necessary. 
Keep  down  volunteer  plants  upon  which  the  weevils  can  breed. 


CHAPTER  XX 
INSECTS  INJURIOUS  TO  THE  STRAWBERRY  * 

The  Strawberry  Root-louse  f 

If  bare  spots  are  found  in  the  strawberry  bed  and  the  neigh- 
boring plants  are  unhealthy,  the  presence  of  the  root-louse  may 
be  suspected,  especially  if  ants  are  abundant  around  the  plants. 
If  present,  the  small  dark  green  or  blackish  aphids  will  be  found 
clustered  on  the  roots  and  stems,  caus- 
ing the  plants  to  wither  and  die.  The 
individual  aphid  is  only  about  one- 
twentieth  inch  long,  and  deep  bluish  or 
greenish-black  when  mature,  the  young- 
er stages  being  lighter,  and  somewhat 
pear-shaped  as  shown  in  Fig.  324. 

Injury  by  this  pest  was  first  noted  in 
southern  lUinois  in  1884  and  a  few  years 
later  it  became  troublesome  in  Ohio.  In 
the  late  '90s  it  ruined  many  beds  on  the  Fig.    324. — The    strawberry 

Maryland-Delaware  peninsula  and  be-      ^5l^^"J?"^^.    ^,^P^^"?  Mbesi 
,..,,.     ,^        -  ^.  VVeed) ;  wingless  viviparous 

came  estabhshed  m  New  Jersey,  bince  female  of  late  summer- 
then  it  has  become  distributed  on  plants  greatly  enlarged, 
throughout  most  of  the  states  east  of  the  Rockies,  injury  having 
been  noted  in  New  Hampshire,  Michigan,  Minnesota,  Kansas, 
Texas,  and  Kentucky.  Injury  is  most  severe  on  light,  sandy 
soils  and  the  pest  rarely  becomes  very  troublesome  on  heavier 
soils.  Injury  is  also  more  or  less  periodic,  the  aphids  almost 
disappearing  after  doing  serious  injury  for  two  or  three  years. 
Fortunately  the  strawberry  is  the  only  food  plant  and  the  root- 
Uce  found  on  other  crops  are  entirely  different  species. 

*  See  L.  Brunor,  Report  Nebraska  Horticultural  Society,  pp.  49-100; 
J.  B.  Smith,  Bulletin  225,  N.  J.  Agr.  Exp.  Sta.;  A.  L.  Quaintance,  Bulletin 
42,  Fla.  Agr.  Exp.  Sta.;  S.  A.  Forbes,  13th  Report  State  Ent.  of  111.,  pp. 
60-180. 

^  Aphis  forbesi  Weed.  Family  Aphididae.  See  Sanderson,  Bulletin  49, 
12th,  13th  and  14th  Reports,  Del.  Agr.  Exp.  Sta. 

389 


390         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Life  History. — The  winter  is  passed  in  the  egg  stage,  the  eggs 
being  black  and  shining  and  located  on  the  stems  and  on  the 
midribs  of  the  leaves.  The  eggs  hatch  early  in  the  spring  and 
the  young  aphids  feed  on  the  young  leaves  in  the  crown.  This 
generation  is  composed  of  wingless  females  which  give  birth  to 


Fig.  325. — Strawberry  root-lice  clustered  on  small  rootlets  from  crown  of 
plant — greatly  enlarged. 

living  young  and  this  method  of  reproduction  continues  until 
fall  when  males  appear  and  the  eggs  are  again  produced.  Shortly 
after  the  aphids  have  become  active  the  ants  appear  and  carry 
many  of  the  young  aphids  down  and  place  them  on  the  roots 
of  the  plants.  This  ant  is  the  same  as  the  one  which  harbors 
the  corn-root  aphis.  (See  page  152.)  On  the  roots  of  the  plant 
the  aphids  cause  the  most  of  the  damage,  weakening  and  even 
killing  the  plants.  They  are  transferred  from  plant  to  plant 
by  the  ants  in  the  underground  stage  while  above  ground  winged 
forms  which  fly  to  fresh  food  plants  appear  from  time  to  time. 
Control. — The  aphid  is  largely  kept  in  check  by  parasitic 
enemies  similar  to  those  described  as  attacking  the  "green-bug" 


INSECTS  INJURIOUS  TO  THE  STRAWBERRY 


391 


and  so  rarely  becomes  a  serious  pest  or  remains  so  for  a  period 

of  years. 

The  best  method  of  avoiding  loss  is  to  set  out  uninfested 
plants  on  land  as  far  removed  from  infested  beds  as  possible. 
Plants  can  be  freed  from  the  lice  by  dipping  them,  after  the 


326. — Egt;s  of  strawberry  root-louse  or  Fig.  327. — Strawberry  root-lice  which  have 
leaf  stem.  been  killed  by  parasites,  with  one  of  the 

little  parasitic  flieswhichhasjustemerged. 

eggs  have  all  hatched,  in  a  solution  of  tobacco.     Plants  lasiy 

also  be  freed  from  aphids  by  fumigation  with  hydrocyanic  acid 

gas  (see  Delaware  bulletin  by  the  senior  author).     The  aphids 

in  an  infested  bed  may  be  largely  destroyed  in  the  spring '  by 

scattering  straw  over  the  bed  and  burning  before  growth  has 

started.     There  is  httle  danger  of  injury  to  the  plants  if  this 

is  properly  done. 

The  Strawberry  Crown-borer  * 

Strawberry  plants  are  often  dwarfed  or  killed  by  a  small  white 

larva  which  mines  out  the  interior  of  the  crown,  hollowing  it  out 

from  the  bases  of  the  leaves  to  the  larger  roots.     Usually  but 

one  grub  is  found  in  a  plant,  and  it  looks  very  much  like  a  small 

*  Tyloderma  fragrance  Rilev.  Family  Curculionidoe.  See  S.  A.  Forbes, 
12th  Report  111.  State  Ent.,  p. "^64;  13th  Report,  p.  142;  H.  Garman,  Bulletin 
80,  Ky.  Agr.  Exp.  Sta..  n.  2fil. 


392         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

white  grub  as  it  lies  curled  in  its  burrow.  It  is  only  about  one- 
quarter  inch  long,  and  legless,  the  body  being  white  and  the  head 
yellowish  brown.     The  adult  beetle  is  a  small  snout-beetle  about 


Fig.  328. — A  Delaware  strawberry  bed  in  summer  of  1900,  Rllo^^■ing  injury 
by  the  strawberry  root-louse. 

one-fifth  inch  long,  of  a  dark  color,  with  head  and  thorax  nearly 
black,  and  on  each  wing-cover  are  three  black  spots,  the  middle 

one  being  the  largest  and 
separated  from  the  others  by 
pale  lines.  According  to 
Professor  Garman  the  wings 
are  too  small  to  be  used  for 
flight  and  this  doubtless  ac- 
counts for  the  slow  spread 
of  the  pest.  Injury  has  been 
■J»;»r  Ril7yrrk""  r^;  reported  from  Illinois,  Ken- 


tucky,  Missouri,  and  Neb- 


FiG.  329.- 
loderma 
beetle — enlarged.     (After  Riley.) 

raska,  but  as  the  larvae  might  be  readily  shipped  in  plants,  it  is 

quite  probable  that  it  has  become  generally  distributed  but  has 

not  done  sufficient  injury  to  attract  attention. 

Life  History. — The   beetles  appear  during  the  latter  part  of 

summer  and  fall  and  hibernate  over  winter  in  the  soil,  emerging 

early  the  next  spring.    The  eggs  have  not  been  observed,  but  are 


INSECTS  INJURIOUS  TO  THE  STRAWBERRY  393 

undoubted!}^  laid  on  the  crown  between  the  bases  of  the  leaves 
in  late  spring.  The  larvae  develop  in  the  crowns  and  become  full 
grown  by  midsummer  or  August  when  they  pupate  in  the  cavities 
formed  and  the  adult  beetles  emerge  in  late  summer  and  fall. 
There  seems  to  be  but  one  generation  a  year.  Old  plants  are 
worst  injured,  and  runners  formed  late  in  the  season  are  usually 
free  from  the  pest,  as  eggs  are  probably  not  laid  after  June. 

Control. — Frequent  rotation,  plowing  up  the  bed  after  one 
or  two  crops,  will  largely  prevent  the  pest  becoming  estabhshed. 
Where  the  insect  is  well-estabHshed  in  old  beds,  it  will  be  well 
to  secure  plants  from  beds  known  to  be  free  from  the  pest  and 
to  plant  new  beds  at  some  distance  from  the  old  ones.  Infested 
beds  should  have  the  plants  plowed  out  and  raked  up  and  burned 
as  soon  as  possible  after  the  fruit  is  harvested  and  before  August. 
Owing  to  the  fortunate  fact  that  the  beetle  cannot  fly  from  field 
to  field,  if  the  above  measures  are  consistently  carried  out 
there  should  be  no  trouble  in  controlhng  the  injury. 

Strawberry  Rootworms  * 

The  larvae  of  three  species  of  common  leaf-beetles  often  feed 

upon  the  roots  of  the  strawberry  and  are  easily  mistaken  for  the 

crown-borer  or  for  small  white  grubs.     They  may  be  distinguished 

from  the  former  by  having  three  pairs  of  small  thoracic  legs  just 

back  of  the  head,  and  from  the  latter  by  their  being  much  thicker. 

These  rootworms  are  from  one-eighth  to  one-sixth  inch  long, 

whitish,   with  brownish  heads,   and  usually  feed  on  the  roots 

externally,   though  sometimes  boring  into  them  or  the  crown. 

Dr.  Forbes  *  has  indicated  the  structural  differences  by  which 

they  may  be  separated  and  shows  that  their  life  histories  are 

quite  dissimilar.     "The  larva  of  Colaspis  appears  early  in  the 

season,  and  does  its  mischief  chiefly  in  the  months  of  April  and 

May,  the  beetles  beginning  to  emerge  in  June.     That  the  eggs 

are  laid  in  the  preceding  year  is  highty  probable,  in  which  case 

the  species  hibernates  in  the  egg.     Typophorus,   on    the  other 

hand,  certainly  passes  the  winter  as  an  adult,  doubtless  laying 

its  eggs  in  spring,  and  making  its  principal  attacks  upon  the 

plants  in  June  and  July,  the  beetles  emerging  in  the  latter  part  of 

*  Typophorus  canellus  Fab.,  Colaspis  brunjiea  Fab.,  Graphops  pubescens 
Mels.     Famih'  Chrysomelidce .     See  Forbes,  I.e.,  p.  150. 


394  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


July  and  early  in  August.    Graphops  hibernates  in  the  larval  con- 
dition, pupates  in  the  spring,  and  emerges  in  May  and  June.     The 

''I     eggs  are  probably  laid  in 


Fig.  330. — The  strawberry  root-borer  (Typo- 
phorus  canellus  Fab.) :  adult  and  larva — very 
greatly  enlarged,  hair  line  at  right  of  beetle 
shows  natural  size.     (After  Pettit.) 


July,  and  the  larvae  make 
their  attack  upon  the 
plant  in  August  and  Sep- 
tember. .  .  "  —  Forbes. 
Thus  the  larvae  of  the 
three  species  may  be 
found  throughout  the 
season  where  all  occur. 
The  beetles  are  about 
one-eighth  inch  long  and 
may  be  distinguished  as 
follows,  according  t  o 
Bruner:  "Colapsis  brun- 
nea  is  usually  of  a  yel- 
lowish clay  color,  but 
ranges  to  yellowish- 
brown.  The  body  is 
smooth  but  not  shining. 
Typophorus  canellus  is 
usually  shiny,  black 
above,  varying  to  brown, 
with  four  black  blotches 
on  the  wing-covers.  The 
legs  and  antennae  are 
always  pale.  Graphops 
pubescens  is  either  green 
or  purple  with  a  bronze 
metalUc  sheen,  and  has 
the  entire  body  more  or 
less  covered  with  a  gray 
pubescence."  The  pupae 
are  all  found  in  earthen 
cells  among  the  roots  of 
the  plants.  The  beetles  of 
allthreespeciesfeed  on  the 
foliage  and  when  numer- 
ous will  attract  attention. 


INSECTS  INJURIOUS  TO  THE  STRAWBERRY 


395 


Control. — Whenever  the  plants  are  not  in  fruit,  the  beetles 
may  be  destroyed  by  sprajdng  with  3  pounds  of  arsenate  of 
lead  per  barrel,  preferably  applied  with  Bordeaux  mixture. 
Where  the  plants  are  customarily  sprayed  with  Bordeaux  mix- 
ture for  leaf  diseases  arsenicals  may  be  added  and  will  probably 
control  this  and  other  strawberry  pests.  Badly  infested  fields 
should  be  plowed  under  deeply  as  soon  as  the  crop  is  secured 
and  new  beds  should  be  planted  at  some  distance  from  them. 


The  Strawberry  Saw-fly  * 

Occasionally  the  strawberry  leaves  are  skeletonized  by  yellow- 
ish or  greenish  "worms"  one-half  to  three-quarters  of  an  inch 
long  when  full  grown.  The  head  is  yellow  with  two  brown  spots 
on  the  side  and  one  or 
two  on  top,  and  there 
are  eight  pairs  of  yel- 
lowish abdominal  pro- 
legs,  in  addition  to  the 
true  thoracic  legs, 
which  at  once  disting- 
uish the  saw-fly  larvae 
from  true  caterpillars. 
The  adult  saw-flies  are 
about  one-quarter  inch 
long,  with  two  pairs  of 
blackish,  well-veined 
wings  which  are  folded 
over  the  abdomen  when 
at  rest.  The  body  is  black,  with  a  row  of  lighter  spots  on  either 
side  of  the  abdomen.  The  flies  emerge  in  late  April  in  Missouri  or 
about  a  fortnight  before  the  plants  flower  freely.  The  eggs  are 
inserted  just  beneath  the  epidermis  of  the  leaves  and  hatch  in 
about  two  weeks,  just  as  the  plants  begin  to  bloom.  The  larva) 
eat  holes  in  the  leaves  and  "where  numerous,  they  will  defoliate 
the  plants  to  such  an  extent  as  to  injure  greatly  or  completely 
destroy  the  crop  of  fruit,  and  may  even  kill  the  plants  them- 

*  Harpiphorus   maculatus   Norton.      Family    Tenthredinidce.     See   J.    M. 
Stedman,  Bulletin  54,  Mo.  Agr.  Exp.  Sta. 


Fig.  331. — The  strawberry  saw-fly  (Harpiphorus 
maculatus  Norton):  1,  2,  pupa;  3,  5,  adult  flies; 
4,  6,  larvae;  7,  cocoon;  9,  egg — all  enlarged. 
(After  Riley.) 


396         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

selves."  When  at  rest  or  disturbed  the  larvae  coil  themselves  up 
in  a  spiral  on  the  under  side  of  the  leaf  as  shown  in  Fig.  331,  but 
if  suddenly  disturbed  they  will  often  drop  to  the  ground.'  By 
the  last  of  May  the  larvse  are  full  grown  and  enter  the  soil,  where 
they  make  small  cells,  lined  with  a  gummy  substance,  and  in  them 
hibernate  until  the  next  spring,  when  they  pupate  and  the  adult 
flies  emerge. 

Injury  by  the  saw-fly  has  been  reported  from  the  Northern 
and  Central  States  from  Missouri  and  Nebraska  to  Maine. 

A  nearly  related  species  *  with  almost  identical  habits  has 
done  similar  injury  in  Iowa,  IlUnois  and  Indiana.  The  larvae 
are  a  deep  green,  much  wrinkled,  with  a  blackish  stripe  along 
the  back  and  an  obscure  blackish  stripe  on  each  side,  and  the 
head  brown. 

Control. — Inasmuch  as  the  larvae  commence  to  hatch  just  as 
blooming  commences  Professor  Stedman  has  shown  by  experi- 
ments that  spraying  the  foliage  at  this  time  with  arsenicals  will 
entirely  protect  it  from  the  larvae.  If  they  commence  work 
before  their  presence  is  noticed,  the  foliage  may  be  sprayed 
until  the  first  berries  are  about  one-third  grown  without  any 
danger  of  poisoning  them.  Hellebore,  1  pound  to  3  gallons  of 
water  was  also  effective,  as  was  dusting  with  pyrethrum. 
Although  there  may  be  some  prejudice  against  the  use  of  arsen- 
icals, where  properly  applied  at  the  right  time  there  is  no  reason 
why  they  should  not  be  used. 

The  Strawberry  Leaf-roller  f 

Where  leaves  are  found  folded  together,  many  of  them  being 
dry  and  brown,  the  small  green  caterpillars  found  feeding  within 
the  folds  are  probably  those  of  the  Strawberry  Leaf-roller.  It 
is  a  European  insect,  though  it  is  not  injurious  there,  and  the 
first  record  of  injury  in  this  country  was  made  by  Dr.  C.  V. 
Riley  in  1869,  who  stated  that  in  one  place  in  Missouri  it  destroyed 
ten  acres  so  completely  as  not  to  leave  enough  plants  to  set  a 
half  acre.  "Since  that  time,"  says  Dr.  J.  B.  Smith,  "the  insect 
has  been  frequently  mentioned  as  injurious  in  many  parts  of  the 

*  Monostegia  ignota  Norton.  See  F.  W.  Mally,  "Insect  Life,"  Vol.  II, 
p.  137. 

t  Ancylis  comptana  Frohl.  Family  Tortricidoe.  See  J.  B.  Smith,  Bulle- 
tins 149  and  225,  N.  J.  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  THE  STRAWBERRY  397 

country,  but  rarely  is  it  troublesome  for  more  than  a  year  or 
two  in  succession.  It  is  always  inclined  to  be  local  and  its 
ravages  do  not  often  extend  over  wide  areas." 

Life  History. — The  moths  appear  in  the  strawberry  fields 
during  early  May  in  New  Jersey  and  commence  to  lay  eggs,  the 
moths  being  found  in  the  fields  for  about  a  month.  The  eggs  are 
laid  on  the  imder  surface  of  the  half-grown  leaves.  They  ai-e 
broadly  oval  or  roimd,  much  flattened,  of  a  pale  green  color  and 
about  one-fiftieth  inch  in  diameter.  They  are  laid  in  the  fine 
netting  of  the  leaf,  in  which  they  are  seen  with  great  difficulty. 
The  larvae  hatch  in  from  five  to  seven  days.  The  young  cater- 
pillar feeds  on  the  upper  surface  of  the  leaf  for  a  day  or  two, 


Fig.    332. — The   strawberry   leaf-roller   moth    {Ancylis  comptana   Frohl.) — 
enlarged.     (After  J.  B.  Smith.) 

eating  into  and  along  the  midrib  to  weaken  it.  The  young  larva 
is  at  first  a  light  green  color  with  a  large  head  and  long  hair, 
which  becomes  less  noticeable  as  it  grows. 

It  soon  commences  to  draw  the  edges  of  the  leaf  together, 
folding  the  upper  surface  on  the  midrib,  holding  it  together  by 
numerous  strands  of  fine  silk.  The  insect  then  spins  a  partial 
tube  or  Hning  inside,  in  which  it  remains  until  the  moth  develops. 
Unless  disturbed  the  larva  does  not  leave  this  folded  leaf,  and  all 
the  feeding  is  done  out  of  the  reach  of  sprays.  The  larva  becomes 
full  grown  in  about  four  weeks,  when  it  is  about  half  an  inch  long 
and  of  a  dark-green  color,  until  just  before  pupation,  when  it 
becomes  more  yellowish.  The  head  and  thoracic  shield  are 
shining  brown,  and  the  small  bodj^  tubercles  are  sUghtly  hghter. 
The  larvae  are  slender  and  very  active,  wriggling  violently  when 
disturbed  or  taken  from  their  webs. 

''  Pupation  occurs  in  the  tube  made  by  the  larva.  The  pupa 
itself  is  brownish-yellow,  without  obvious  processes  or  protuber- 


398         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


ances,  and  a  little  more  than  one-fourth  an  inch  long."  The  pupal 
stage  lasts  about  ten  days,  thus  giving  about  forty-two  to  fifty 
days  for  the  complete  life  cycle  from  egg  to  adult. 

The  moths  of  the  second  brood  appear  late  in  June  and  during 
July.  This  brood  is  much  more  abundant  on  blackberry  and 
raspberry  than  on  strawberry  plants.     The  moths  of  the  third 


Fig.  333.— Strawberry  leaf  folded  by  the  leaf-roller.     (After  J.  B.  Smith.) 

brood  appear  in  August.  They  are  comparatively  few  in  number 
and  also  seem  to  prefer  blackberry  and  raspberry.  Young  larvse 
are,  however,  to  be  found  on  strawberries  in  September.  ''Accord- 
ing to  the  account  given  by  Riley,  the  larvae  change  to  pupae 
late  in  September  and  remain  during  the  winter  in  that  state." 
Dr.  Smith  states  that  he  has  not  observed  this  personally.  In 
Delaware  we  have  found  full-grown  larvse  in  folded  leaves  in 
midwinter,  so  that  possibly  some  of  them  at  least  do  not  pupate 
until  spring. 

"  The  adult  moth  is  small,  measuring  with  expanded  wings 
about  two-fifths  of  an  inch.     In  general  color  it  is  somewhat 


INSECTS  INJURIOUS  TO  THE  STRAWBERRY  399 

reddish-brown,  the  fore-wings  streaked  and  spotted  with  black 
and  white  as  shown  in  the  illustration.  When  the  wings  are 
folded,  the  dark  area  at  the  base  forms  a  somewhat  conspicuous 
deeper  brown  patch  in  the  middle  of  the  back.  The  hind-wings 
are  of  a  soft,  dark  smoky  gray,  and  both  wings  have  long  fringes. 
The  insects  fly  readily  during  the  middle  of  the  day,  and  run 
rapidly  on  the  leaves,  diving  to  the  under  side  or  into  a  fold  so 
quickly  that  it  requires  close  watching  to  follow  their  move- 
ments. From  the  fact  that  newly  set  fields  are  often  infested,  it 
is  probable  that  they  fly  for  some  distance  to  seek  their  food 
plant." — Smith. 

''A  badly  infested  strawberry-patch  begins  to  look  scorched 
early  in  June,  and  before  the  middle  of  that  month  appears  as  if 
a  fire  had  been  over  it.  The  fruit,  deprived  of  the  food  prepared 
by  the  foHage,  stops  growth,  ripens  undersized  or  prematurely,  or 
shrivels  up  altogether,  even  before  it  colors."  "Often  every 
lobe  on  a  leaf  will  be  folded,  and  occasionally,  when  infested 
leaves  cover  or  touch,  an  irregular  mass  of  foliage  is  bundled 
up  in  which  as  many  as  six  or  eight  larvae  may  be  found. 

"On  blackberry  not  so  large  a  part  of  the  leaf  is  involved, 
and  frequently  only  the  tip  of  one  of  the  leaflets  is  webbed  up. 
Furthermore,  the  injury  is  more  local,  and  only  that  part  that 
is  actually  eaten  is  harmed.  The  total  amount  of  food  really 
devoured  is  very  small,  and  were  it  not  for  the  manner  of  feeding, 
which  interferes  with  the  nutrition  of  the  leaf,  the  strawberry 
could  easily  spare  tissue  for  all  these  caterpillars  that  ever  infest 
it.  On  the  raspberry  the  habit  is  yet  different.  Here  the  larva 
gets  into  a  partly  opened  tip  and  webs  it  together  so  securely 
as  to  check  growth.  The  actual  eating  shows  a  rusty  space  on 
the  upper  side  of  the  leaf,  and  not  much  more  harm  is  done." 

Cotitrol. — As  stated  above,  the  young  caterpillar,  just  after 
it  is  hatched,  goes  to  the  upper  surface  of  the  leaf  and  feeds  there 
exposed  for  a  day  or  two  before  folding  the  leaf.  "It  must  be 
the  object  of  the  grower  to  poison  the  foliage  so  early  in  the  season 
that  when  the  young  caterpillar  starts  feeding,  it  can  find  no 
foliage  it  can  safely  eat.  Therefore,  as  soon  as  moths  are  found 
flying  in  fair  numbers,  spray  with  arsenate  of  lead.  Experiments 
in  New  Jersey  have  shown  that  complete  control  may  be  secured 
with  one  application  if  this  is  thorough  and  applied  at  the  right  time. 


400         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


''If  for  any  reason  no  timely  applications  were  made  and  the 
fields  become  badly  infested,  nothing  practical  can  be  done  imtil 
the  crop  is  off.  Then  mow  the  beds,  rake  off  all  the  foHage,  and 
burn  it.  You  will  burn  with  it  all  the  larvae  and  pupse  that  are 
then  unchanged.  This  lessens  the  number  of  moths  that  come 
to  maturity  and  so  helps  somewhat  for  the  following  year." 

The  Strawberry  Weevil  * 

If  the  buds  appear  to  be  "stung"  so  that  they  wither,  and 
if  many  of  the  stems  are  cut  so  that  the  buds  drop  to  the  ground, 
the  strawberry  weevil  is  the  probable  cause 
of  the  damage.  This  little  weevil  is  only 
about  one-tenth  inch  long  and  so  is  often 
unnoticed,  and  the  loss  is  attributed  to  other 
causes.  The  weevil  varies  from  nearly 
black  to  dull  red,  with  a  dark  spot  just  back 
of  the  centre  of  each  wing-cover.  The  head 
is  prolonged  into  a  slender  curved  snout, 
about  half  as  long  as  the  body.  The  species 
is  found  in  most  of  the  States  east  of  the 
Rockies,  but  injury  has  been  mosts  evere  in 
the  Middle  and  Northern  States. 

Life  History.— The  weevils  hibernate  over 
winter  and  appear  in  spring  a  few  days  be- 
fore the  earliest  staminate  varieties  com- 
mence to  bloom.    Others  emerge  during  the 
Fig.    334. —  The    straw-         ,  j.u     u   j.    iu  j.    •    •         •    j 

berry    weevil    (Antho-  ^i^xt  month,   but  the  most  mjury  is  done 

nonius  signatus  Say.)—  within  the  next  two  weeks.  The  injury  is 
and '^Chittenden'^  u!  *S^  done  by  the  females,  which  eat  small  holes 
Dept.  Agr.)  through  the  outer  husk  or  corolla  of  nearly 

matured  buds,  and  in  these  little  cavities  deposit  their  eggs.  The 
stem  of  the  bud  is  then  cut  so  that  it  hangs  by  a  mere  thread  and 
soon  falls  to  the  ground.  By  severing  the  stem  the  development  of 
the  bud  is  arrested,  thus  preventing  the  outer  covering  from  un- 
folding and  holding  the  eggs  and  larvae  in  the  pollen,  on  which  they 
feed,  and  by  falling  to  the  ground  the  bud  remains  moist  and  will 
not  dry  up  as  it  would  on  the  stem.     The  eggs  hatch  in  from  six 

*  Anthonomus  signatus  Say.  Family  Curculionidae.  See  F.  H.  Chitten- 
den, Circular  21,  Div.  Ent.,  U.  S.  Dept.  Agr.;  J.  B.  Smith,  Bulletin  225, 
N.  J.  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  THE  STRAWBERRY 


401 


to  seven  days  and  the  small  whitish  larvae  feed  on  the  pollen  and 
later  on  the  harder  parts  of  the  buds.  Three  or  four  weeks  are  re- 
quired for  a  larva  to  become  full  grown.  It  then  forms  a  little  cell 
in  the  bud,  in  which  the  pupal  stage  is  passed  in  from  five  to  eight 
days,  when  the  adult  beetle  emerges  and  cuts  its  way  out.  Thus 
the  complete  life  cycle  occupies  about  a  month  and  in  the  District 
of  Columbia  the  new  generation  of  beetles  appears  during  June. 
They  are  frequently  found  in  large  numbers  on  strawberry  flowers 
and  on  those  of  the  horse 
mint  {Monarda  fistulosa), 
but  the  beetles  soon  seek 
hibernating  quarters,  there 
being  but  one  generation 
a  year. 

Control. — As  the  larvae 
feed  upon  the  pollen  of  the 
buds  of  staminate  varieties, 
the  staminate  varieties  are 
most  injured,  and  injury 
may  be  avoided  by  growing 
as  few  rows  of  staminate 

varieties   as  are  necessary  Fig.  335.— The  strawberry  weevil:  a,  6,  spray 

for  fertiUzing  the  rest  of  the      showing  work  in  bud  and  stem— natural 

°  size;  c,  outline  oi  egg;  (/,  larva;  e,  head  of 

bed.     Indeed  the  very  early     same;  /,  pupa;  g,  bud  opened  to  show  egg 

staminate  varieties  might  Cee^th';"„UTe?^^^,e?  ciSden! 
be  used  as  a  trap  crop  for  U.  S.  Dept.  Agr.) 
attracting  the  weevils,  which  might  be  destroyed  by  covering 
the  rows  with  straw  and  burning,  or  possibly  by  spraying  with 
arsenicals.  By  planting  rows  of  early  varieties,  which  flower 
freely  and  produce  an  abundance  of  pollen  near  woods  and 
fence-rows  where  the  beetles  have  hibernated  and  appear  first, 
they  might  be  effectively  trapped,  and  then  destroyed.  Although 
the  larvae  cannot  be  reached  with  any  insecticide,  the  beetles 
feed  more  or  less  on  the  buds  and  foliage,  and  further  experiments 
should  be  made  in  spraying  for  them  with  arsenicals.  Dr.  T.  J. 
Headlee  (Circulars  56  and  65,  New  Jersey  Agr.  Exp.  Station) 
recommends  dusting  the  plants  with  arsenate  of  lead  powder 
one  pound  mixed  with  five  pounds  sulphur  dust.     On  a  large 


402         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

scale  this  should  be  applied  with  power  dusters  as  the  hand 
dusters  have  not  proven  so  successful.  Begin  applications  as 
soon  as  the  weevils  appear,  not  later  than  the  first  of  May. 

Lead  arsenate  apphed  as  a  spray  has  seemed  to  give  good 
control  in  some  smaller  tests  and  should  be  at  least  as  effective 
as  the  dust. 

The  destruction  of  all  trash  and  rubbish  in  and  around  the 
fields  during  the  winter  will  destroy  some  of  the  hibernating 
weevils,  and  it  will  be  well  to  avoid  mulching  the  beds  where 
the  beetle  is  troublesome,  if  the  mulch  is  not  absolutely  neces- 
sary, as  it  furnishes  them  the  best  hibernating  quarters. 


CHAPTER  XXI 


INSECTS  INJURIOUS  TO  RASPBERRY  AND  BLACKBERRY  * 
The  Raspberry  Root-borer  f 

The  larvae  of  the  Raspberry  Root-borer  make  tunnels  in  the 
roots  and  lower  stems  of  raspberry  and  blackberry,  sometimes 
completely  girdling  the  stem  at  the  crown,  so  that  the  name  of 
blackberry  crown-borer  has  also  been 
used.  The  full-grown  larva  is  from  1  to 
1^  inches  long,  yellowish-white,  with 
brownish  head,  and  the  tips  of  the  small 
thoracic  legs  also  brownish.  The  parent 
insect  is  one  of  the  clear-winged  moths, 
which  fly  by  day  and  closely  resemble 
wasps,  and  is  nearly  related  to  the  peach- 
and  squash-borers.  The  female  is  much 
the  larger  and  is  shown  natural  size  in 
Fig.  336.  The  body  is  black  with  yellow 
rings,  and  the  legs  are  yellowish.  The 
wings  are  transparent  except  a  bronze-  Fig.  336.— The  raspberry 
brown  margin  and  a  narrow  band  across  root-borer  {Bemhecia 
the  fore-wings  about  one-third  from  the  ZZ^'moih^h'iL^le 
tip.  moth  —  natural  size. 

Life  History. — The  moths  appear  in  (After  Riley.) 
late  August  and  September  and  the  females  deposit  their  eggs 
upon  the  lower  edge  of  the  leaves.  The  egg  is  oval,  about  one- 
sixteenth  inch  long,  deep  brownish-red  in  color.  A  female  lays 
about  140  eggs,  which  are  deposited  singly.  They  hatch  in  Sep- 
tember and  the  young  larvsB  crawl  down  the  stems  and  bore 
under  the  bark.      Here    they  may  either  make  a  small  blister- 

*  See  F.  M.  Webster,  Bulletin  45,  Ohio  Agr.  Exp.  Sta.;  J.  B.  Smith,  12th 
Report  N.  J.  Agr.  Exp.  Sta. 

t  Bemhecia  maerginata  Harr.  Family  Sesiidoe.  See  J.  B.  Smith,  Bulletin 
N.,  N.  J.  Agr.  Exp.  Sta.,  p.  9;  W.  H.  Lawrence,  Bulletin  63,  Wash.  Agr.  Exp. 
Sta. 

403 


404         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


like  cavity  and  hibernate  over  winter,  or  if  hatched  earlier  they 
may  feed  on  the  sap  wood  or  occasionally  bore  into  the  stem  and 
become  one-quarter  inch  or  more  long  before  winter.  The  next 
season    the    larvae  bore  in  the   lower   stem   and  roots,    but  the 

nature  of  the  injury  differs 
as  observed  in  different 
places.  In  New  Jersey,  Dr. 
J.  B.  Smith  states  that  the 
larvse  girdle  the  stem  at  the 
crown,  causing  the  plants  to 
die.  In  spring  they  aban- 
don the  old  wood  and 
attack  new  shoots,  but  he 
observed  none  entering  the 
stem.  In  Washington,  the 
infested  plants  seldom 
show  any  signs  of  the  pres- 
ence of  the  borers  other 
than  a  poor  growth,  though 
occasionally  a  few  hills  will 
die  where  the  roots  have 
been  badly  riddled  by  the 
larvse,  the  injury  being 
mostly  in  the  roots.  "The 
borer,"  according  to  Law- 
rence, "first  enters  the 
roots  and  tunnels  through 
them  promiscuously  until 
the  second  spring,  and  then 
directs  its  course  upward, 
entering  and  eating  the  pith 
of  the  cane  for  a  distance  of 

Fig.  337.-lR^pbe^rry  root-borer  (Bcmhccia  ^^e  to  five  inches."  At  the 
marginata  Harr.):  a,  female  and  male  end  of  the  first  summer  the 
larvai,    full  grown;    h,  male    and    female  ,  •     onp-hnlf   to  three- 

pupaj;  c,  female,  and  d,  male  moths  rest-  ^^^^^  ^^  P"^  ^^"^  ^°  tnree- 
ing  on  leaf;  e,  e,  eggs — slightly  reduced,  quarters  inch  long.  By  the 
(After  Lawrence.)  ^-^^jj^  ^f    ^^^  ^^^^^^  ^^^_ 

mer  the  larva  is  full-grown  and  bores  an  exit  hole  through  the 
wood  and  bark  just  above  the  crown,  leaving  the  hole  covered  by 


INSECTS  INJURIOUS  TO  RASPBERRY  AND  BLACKBERRY     405 


tlie  epidermis  only    The  larva  then  descends  into  the  tunnel  and 
pupates. 

The  pupa  is  about  three-quarters  inch  long,  reddish-brown 
the  head  bears  a  sharp-pointed  process,  and  each  abdominal 
segment  bears  two  transverse  rows  of  sharp  teeth.  By  means 
of  these  the  pupa  wriggles  itself  out  of  the  burrow  until  it  pro- 
jects from  the  aperture,  and  the  adult  moth  emerges.  This  insect 
occurs  tlu-oughout  the  Middle  and  Northern  States  east  of  the 


Fig.  33S. — Work  of  the  raspbern^  root -borer:  a,  two  canes  with  empty  pupa 
cases  projecting  from  burrows;  h,  canes  showing  opening  of  tunnel 
through  which  pupae  have  wriggled  out.     (After  Lawrence.) 

Rockies,  is  injurious  in  Washington  and  around  Vancouver,  B.  C, 
and  has  been  observed  in  Colorado  and  New  Mexico. 

Control. — The  only  method  of  control  is  to  pull  up  the  infested 
canes,  root  and  branch,  and  destroy  them  by  burning.  As  this 
is  the  only  means  of  controlling  several  pests  of  cane  fruits,  the 
canes  should  always  be  gone  over  in  spring  and  those  showing 
any  injury  removed. 

The  Raspberry  Cane-borer  * 

If  the  tips  of  the  j^oung  shoots  of  raspberry  and  blackberry 
are  found  withered  and  djdng  they  have  probably  been  girdled 
by  the  cane-borer.  The  adult  beetle  is  about  one-half  inch  long, 
with  a  slender,  cylindrical  body  and  long  antennae,  and  of  a  deep 
black  color  except  the  prothorax,  which  is  yellow  with  two  or 
three  black  spots,  though  these  are  sometimes  lacking. 

*  Oberea  himaculata  OUv.  Family  Cerambycidoe.  See  Comstock  and 
Slingerland,  Bulletin  23,  Cornell  Univ.  Agr.  Exp.  Sta.,  p.  122. 


406 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Life  History. — The  beetles  appear  in  early  summer  and  the 
females  girdle  the  young  tips  by  cutting  two  rings  around  the 
shoot  about  an  inch  apart,  causing  the  tip  to  wither  and  droop. 
Between  these  rings  will  be  found  a  small  dark  spot  where  the 
female  has  inserted  an  egg  in  the  cane.  A  rather  large,  elliptical, 
yellow  egg  is  placed  in  the  pith  of  the  cane  and  in  a  few  days 
hatches  into  a  small  white  grub.  The  larvae  burrow  downward 
through  the  pith  of  the  stems,  the  burrows  winding  from  side 
to  side  and  frequently  penetrating  the  side  of  the  stem,  where 
openings  are  made  every  few  inches,  through  which  long  strings 


Fig.  339. — The  raspberry  cane-borer  (Oberea  himaculata  Oliv.):  adult,  larva, 
and  larval  castings — all  enlarged.     (After  Lugger.) 

of  excrement  are  cast  out.  By  fall  they  are  bored  to  the  base 
of  the  cane,  in  which  they  hibernate  over  winter.  The  full- 
grown  larva  is  about  one  inch  long,  of  a  dull  yellow  color,  with 
a  small  dark-brown  head.  The  body  is  quite  cylindrical  and 
the  segments  constricted  as  shown  in  Fig.  339.  The  pupal  stage  is 
passed  in  the  burrow  during  the  spring.  Although  it  has  been 
generally  assumed  that  the  hfe  cycle  is  passed  in  a  single  year,  there 
is  some  reason  for  believing  that  two  years  may  be  required.  The 
eggs  are  usually  laid  only  in  the  young  tips,  but  Comstock  and 
Slingerland  found  larvae  somewhat  over  half  grown  which  had 
made  burrows  only  two  inches  long  in  old  canes  in  late  July,  and 
Professor  Webster  has  secured  larvae  over   half  grown  in  early 


INSECTS  INJURIOUS  TO  RASPBERRY  AND  BLACKBERRY  407 


June.  Possibly,  therefore,  two  years  may  be  required  for  maturing 
a  generation,  and  the  fact  that  the  pest  does  not  increase  may  be 
due  to  the  cutting  back  of  the  injured  tips  of  the  young  canes. 

Control. — As  soon  as  the  tips  are  seen  to  droop  they  should 
be  cut  off  below  the  point  girdled  and  burned.  When  the  entire 
canes  die  from  the  effect  of  being  tunneled,  they  should  be  cut 
in  late  summer  before  the  larvae  have  gone  to  the  base  to  hiber- 


FiG.  340. — Egg  of  the  rasp- 
berry cane-borer,  showing 
girdhng  of  cane.  (Photo 
by  Headlee.) 


Fig.  341. — Young  grubs  and  exit  hole 
of  the  raspberry  cane-borer.  (Photo 
by  Headlee.) 


nate.     Where  such  measures  are  practised  the  pest  may  be  effec- 
tively controlled. 

The  Striped  Tree-Cricket  * 

Professor  Parrott  has  recently  shown  in  an  interesting  bulletin 

from  the  New  York  station  that  the  tree-cricket  which  most 

frequently  attacks  the  raspberry  is  not,  as  had  been  supposed, 

the  snowy  tree-cricket    {Oecantlius  niveiis   DeG.)  but  a  different 

species,  the  one  named  above.     The  snowy  cricket  confines  its 

attentions  more  to  apple  and  other  tree  fruits. 

*  Oecanthus  nigricornis  Walker.     Family  Gryllidce.     See  Parrott  and  Ful- 
ton, Bulletin  388,  N.  Y.  (Geneva)  Agr.  Exp.  Sta. 


408         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Fig.  342.— The  snowy  tree- 
cricket  (Oecanthus  nigricornis 
Walker):  a,  female;  h,  male. 
(After  Summers.) 


When  the  canes  fail  to  put  out  leaves  in  the  spring  and  are 

found  to  be  dead,  this  often  proves  to 
be  due  to  a  long  ragged  wound  like 
that  shown  in  Fig.  343a.  "If  the 
rough  surface  of  the  wound  be  cut 
away  with  a  knife,  the  injury  will  be 
found  to  consist  of  a  longitudinal 
series  of  punctures  placed  close  to- 
gether. By  spUtting  the  cane  the 
nature  of  the  injury  can  be  seen  even 
better.  Such  a  section  is  shown  at  h 
in  the  figure.  The  punctures  extend 
through  the  woodypart  of  the  cane  in- 
to the  pith,  and  here  there  is  in  each 

an  oblong,  cylindrical  egg.    One  of  these  eggs 

is  represented  enlarged  at  c.      The  insect 

which  thus  seriously  injures  the  raspberry 

canes  in  preparing  a  safe  receptacle  for  its 

eggs   is  a    dehcate  greenish-white   cricket. 

Fig.  342  represents  the  male.  Its  wing-covers 

are  crossed  by  obHque  thickenings  or  ribs, 

which  form  part  of  the  musical  apparatus  of 

the  insect.     The  female,  Fig.  342a,  differs 

somewhat  in  appearance  from  the  fact  that 

the  wing-covers  are  wrapped  closely  about 

the  body,  making  the  insect  much  narrower 

than  her  mate."     (Comstock  and  SHnger- 

land.)     The  cry  of  these  tree-crickets  is  well 

known,  sounding  much  like  that  of  the  katy- 
did, but  is  less  rasping  and  more  monoton- 
ous.    They  are  heard  in  early  evening  until 

well  into  the  night,  and  in  the  North  their 

chirp  is  the  most  noticeable  of  all  the  insect 

noises  at  that  time.     This  species  is  quite  p^^.  343-Raspberry^em 

widely  distributed  and  frequently  oviposits      injured  by  the  snowy 

in  the  tender  twigs  of  fruit  trees,  which  are 

similarly  injured,  and  in  the  stalks  of  cotton 

and  various  woody  weeds. 

Life  History. — The  eggs  are  laid  in  the  fall 

and  hatch  in  the  late  spring.     The  nymphs 


tree-cricket:  a,  wound 
made  by  egg  -  punc- 
tures; h,  longitudinal 
section  through  same 
showing  eggs  in  path ; 
c,  egg  enlarged;  d,  cap 
of  egg,  more  enlarged. 
(After  Riley.) 


INSECTS  INJURIOUS  TO  RASPBERRY  AND  BLACKBERRY   409 


feed  mostly  on  plant-lice  and  other  insects,  as  do  the  adults,  and 
though  they  occasionally  nibble  foliage,  they  are  seldom  in- 
jurious, and  both  nymphs  and  adults  must  be  regarded  as 
beneficial  as  far  as  their  feeding  habits  are  concerned.  In  the 
North  the  nymphs  become  full  grown  late  in  July,  and  there  is 
but  one  generation  a  year,  but  in  Texas  they  become  full  grown 
late  in  June  and  eggs  laid  in  early  July  hatch  in  about  two 
weeks;  nymphs  are  common  in  late  simimer,  and  the  adults  of  the 
second  generation  in  fall. 

Control. — By  examining  the  canes  as  soon  as  the  foliage  starts, 
those  injured  may  be  detected  and  should  be  cut  out  and  burned. 
If  not  numerous  enough  to  do  appreciable  damage  they  may  be 
ignored. 

The  Red-necked  Cane-borer  * 
Sometimes  the  canes  of  raspberry  and  blackberry  are  found 
with  one  or  more  elongate 
galls,  not  over  one-third 
larger  in  diameter  than  the 
normal  cane,  and  usually 
with  numerous  slits,  which 
have  been  called  the 
' '  gouty  gall. ' '  The  infested 
shoots  may  throw  out 
leaves,  but  they  rarely  rip- 
en fruit  and  usually  die 
during  the  season.  By 
opening  the  gall  it  will  be 
found  that  only  the  bark 
has  been  injured  by  a 
spiral  channel  which 
girdles  the  stem  and  causes 
the  gall-hke  thickening  of 
the  bark.  Above  the  swel- 
ling evidence  will  be 
found  of  the  borer's  work 
in  the  pith,  and  from  one 
to  six  inches  above  the 
gall  the  slender  white  larve  Fig-  344.-The  red-necked  cane-borer  (Agrilus 

.  ruficolhs  Fab.) :  beetle,  larva  and  gall — all 

will  be  found  at  work.  much  enlarged.     (After  Riley.) 

*  Agrilus  ruficolhs   Feab.      Family   Buprestidoe.     See  J.  B.   Smith,    12th 
Report  N.  J.  Agr.  Exp.  Sta.,  p.  373;  and  F.  M.  Webster,  I.e.,  p.  000. 


410         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


There  seems  to  be  considerable  difference  in  the  susceptibility 
of  varieties,  Dr.  Smith  observing  that  the  "  Wilson"  and  black- 
cap raspberries  are  badly  infested,  while  the  "Missouri  Mam- 
moth" and  others  were  unharmed. 

Life  History. — The  eggs  are  laid  in  June  and  the  young  larva 
enters  the  bark  at  the  axil  of  a  leaf-stem,  and  eats  around  the 
stem  in  a  long  spiral.  By  early  August  the  galls  commence  to 
form  where  the  bark  has  been  girdled,  though  sometimes  no  gall 
results  from  the  injury,  and  the  larvae  mine  into  the  pith.  The 
larvae  probably  become  practically  full  grown  in  the  fall  and 
remain  in  their  burrows  over  winter,  in  which  they  transform  to 

pupae  in  late  April,  in 
New  Jersey,  and  the 
beetles  emerge  in  late 
May  and  June.  The 
parent  beetle  is  not 
over  one- third  inch 
long,  flattened,  with  a 
small  wide  head,  and 
tapers  at  the  tip  of  the 
abdomen.  It  has  brown- 
ish-black wing-covers 
with  a  bronzy  lustre, 
and  the  neck  and  thorax 
are  coppery-red  or 
brassy.  The  full-grown 

Fig.  345.— Work  of  the  red-necked  cane-borer:  larva  is  five-eighths  to 

a,  tracks  of  young  larvsR  the  bark  sHced  away  three-q  U  a  r  t  e  r  S     inch 

to  show  burrows  and  forming  gall  ridges;  6,  sec-  ■,  •,■,  ■,-, 

tion  through  galls  on  main  cane  and  lateral  -^O^S?      Wltn    a     small 

showing  track  of  larva  through  bark  and  pith  brown    head,   a    much- 
and  pupal  cell.     (After  J.  B.  Smith.)  j    ,  ,, 

^  ^  expanded  prothorax 

which  looks  like  the  head,  and  a  slender,  cylindrical,  white  body, 

surmounted  by  two  slender  brown  horns  at  the  tip  of  the  abdomen. 

This  cane-borer  is  a  native  pest,  very  common  in  wild  rasp- 
berries and  blackberries,  and  occurs  generally  throughout  the 
country. 

Control. — Obviously  it  may  be  readily  controlled  by  cutting  off 
the  infested  canes  below  the  galls  and  burning  them.  This  should 
be  done  any  time  before  May.  Where  wild  canes  are  infested 
near  those  cultivated  they  should  be  included  in  the  pruning. 


<C 


INSECTS  INJURIOUS  TO  RASPBERRY  AND  BLACKBERRY     411 


The  Blackberry  Gall-maker  * 

The  so-called  "pithy  gall"  of  the  blackberry  is  an  elongated, 
pithy  swelling  from  one  to  three  inches  long  and  nearly  an  inch 
in  diameter,  red  or  reddish-brown,  with  the  surface  divided  by 
deep  longitudinal  furrows  into  four  or  five  ridges  or  parts.  The 
gall  is  caused  by  the  larvse 
of  a  small  black  gall-fly, 
which  is  about  one-twelfth 
inch  long,  with  red  feet 
and  antennae  and  four 
transparent  wings,  almost 
lacking  wing-veins.  The 
insect  passes  the  winter  in 
the  larval  stage  in  the  galls, 
and  if  one  be  opened  at 
that  season,  there  will  be 
found  about  the  middle  a 
number  of  cells  about  one- 
eighth  inch  long,  each  of 
which  contains  a  single 
larva.  The  larva  "is 
about  one-tenth  inch  long, 
white,  with  the  mouth- 
parts  reddish,  and  the 
breathing  pores  and  an  oval 
spot  on  each  side  behind 
the  head  of  the  same  color. " 
They  change  to  pupse  in 
spring  and  the  flies  appear  Fig.  346.— The  pithy-gall  of  the  blackberry :  a, 

.     .      .  T-u        u       gall; «,  section  of  same  showing  larvae  in  cells; 

a   little    later.         ihough      c,  larva  enlarged  and  natural  size;  d,  pupa. 
this  gall  is  also  very  com-      (After  Riley.) 

mon  on  wild  canes  it  rarely  does  much  injury. 

Control. — The  affected  canes  should  be  cut  and  burned  during 
the  winter. 

The  Raspberry-cane  Maggot  f 

The  tips  of  young  raspberry  shoots  sometimes  droop  and  wilt 
in  the  spring  in  much  the  same  manner  as  when  affected  by  the 

*  Diastro'phus  turgidus  Bass.     Family  Cynipidop. 

t  Phorbia  rubivora  Coquillet.  Family  Anihomyidce.  See  Slingerland, 
Bulletin  126,  Cornell  Univ.  Agr.  Exp.  Sta.,  p.  54;  W.  H.  Lawrence,  Bulletin 
62.  Wash.  Agr.  Exp.  Sta. 


412         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

cane-borer  later  in  the  season,  and  though  blackberry  shoots  are 
similarly  affected  they  usually  recover,  but  bear  small  gall-hke 
swellings  like  those  shown  in  Fig.  348.     This  is  the  work  of  a 


Fig.  347. — The  raspberry  cane-maggot  (Phorbia  rubivora  Coquillet) :  a,  adult 
female  fly;  much  enlarged;  b,  raspberry  shoots  girdled  by  the  maggot, 
natural  size;  c,  egg  much  enlarged;  d,  tips  of  shoots  each  bearing  an  egg 
in  natural  position  in  the  leaf  axils,  natural  size.     (After  Slingerland.) 

small  white  maggot,  nearly  related  to  and  looking  much  the  same 
as  the  cabbage-maggot  which  girdles  the  inner  bark  of  the  stem. 


INSECTS  INJURIOUS  TO  RASPBERRY  AND  BLACKBERRY     413 


Injury  has  been  observed  in  New  York,  Canada,  Michigan, 
Pennsylvania,  and  recently  it  has  become  a  serious  pest  in  Wash- 
ington, so  that  it  is  undoubtedly  much  more  widely  distributed 
than  the  records  indicate.  The  parent  fly,  shown  in  Fig.  347,  is 
grayish-black,  much  resembling  the  house-fly,  but  slightly  smaller. 
Life  History. — The  flies  appear  in  April  and  deposit  their  eggs 
as  soon  as  the  shoots  are  well  above  ground,  continuing  until  earlv 
June.  The  white  egg  (Fig. 
347,  c)  is  elongate,  about  one- 
fifteenth  inch  long,  and  is  laid 
in  the  axil  of  a  young  leaf  at 
the  tip  of  a  shoot  (Fig.  347,  d). 
The  egg  hatches  in  a  few  days, 
and  the  little  maggot  burrows 
into  the  pith  of  the  shoot,  leav- 
ing a  conspicuous  entrance 
hole,  which  becomes  blackish. 
It  tunnels  downward,  making 
a  small  tortuous  channel,  and 
after  boring  for  a  few  daj'^s 
about  half  way  down  the  shoot, 
it  works  its  way  out  to  just 


Fig.  348. — Gall-like  swelling  one  living 
blackberry  canes  caused  by  the  rasp- 
berry cane-maggot.    (After  Lawrence.) 


beneath  the  bark  and  tunnels  around  the  shoot,  often  in  a  spiral, 
so  as  to  girdle  it  completely,  and  usually  eats  a  small  hole  through 
the  bark  at  this  point.  The  maggot  continues  to  feed  on  the 
pith  at  this  point  so  as  nearly  to  sever  the  shoot,  the  tip  of  which 
soon  wilts  and  droops,  turning  a  deep  blue  color.  On  blackberry 
shoots,  however,  the  bark  is  so  thick  that  although  the  tip  droops 
for  a  few  days,  it  usually  revives  and  the  girdling  forms  a  circular, 
gall-like  swelling,  though  even  blackberries  are  often  killed. 
Affected  shoots  usually  branch  from  below  the  girdled  point, 
making  a  bushy  growth.  Lawrence  states  that  later  in  the 
season  lateral  shoots  are  also  attacked.  He  also  observes  that 
maggots  never  develop  in  living  canes.  The  maggot  continues 
to  burrow  downward  in  the  pith  and  becomes  full  grown  in  June, 
when  it  pupates  at  the  lower  end  of  the  burrow.  The  puparia 
are  to  be  found  in  the  lower  part  of  the  affected  stalk  in  June 
and  July,  but  the  adult  flies  do  not  emerge  until  the  next  spring. 
Control. — As  soon  as  the  young  tips  are  seen  to  droop  they 


414         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

should  be  cut  off  several  inches  below  the  girdled  point  and 
burned.  This  may  be  done  best  late  in  May  or  in  June  after  all 
the  eggs  are  laid. 

The  Raspberry  Saw-fly  * 

Occasionally  raspberry  leaves,  as  well  as  those  of  blackberry 
and  dewberry,  are  skeletonized  in  May  by  small  green,  spiny 
saw-fly  larvae,  which  sometimes  quite  defoliate  the  plant.  Such 
injury  has  been  commonly  noted  in  the  Eastern  and  Central 
States.  The  adult  female  is  a  typical  saw-fly  about  one-quarter 
inch  long  and  with  a  wing  expanse  of  one-half  inch.  The  body 
and  wings  are  black  except  the  second  and  sixth  abdominal  seg- 
ments, which  are  yellowish- white,  and  the  under  side  is  rusty. 
The  male  is  somewhat  smaller  and  is  entirely  black  except  the 
shoulders,  which  are  yellowish-white. 

Life  History. — The  adults  appear  about  the  middle  of  May 
in  central  New  York,  and  the  females  deposit  their  eggs  late  in 
that  month.  The  eggs  are  inserted  just  under  the  cuticle  of  the 
under  surface  of  the  leaf,  and  the  tissue  around  them  turns 
yellowish,  so  that  infested  leaves  soon  become  spotted  on  the  upper 
surface.  The  egg  is  nearly  pear-shaped,  yellowish-white,  about 
one-twentieth  inch  long,  and  hatches  in  seven  to  ten  days.  As 
many  as  twenty-four  eggs  have  been  observed  in  a  single  leaf,  and 
frequently  the  leaves  are  so  spotted  as  to  be  readily  recognized. 
The  young  larva  is  about  one-twelfth  inch  long,  yellowish-white  or 
pale  yellowish-green  and  well  covered  with  spiny  tubercles,  the 
spines  being  first  white  and  later  dark  brown.  The  young  larvse  feed 
on  the  soft  parts  of  the  leaf,  but  as  they  grow  older  all  but  the  midrib 
and  larger  veins  are  devoured.  The  mature  larva  is  about  three- 
quarters  inch  long,  from  light  yellowish-green  to  darkgreen,  closely 
simulating  the  color  of  the  foliage,  and  the  body  is  covered  with 
transverse  rows  of  tubercles,  bearing  a  varying  number  of  strong, 
barbed  spines,  which  are  dark  brown  on  the  back  and  pale  green 
or  white  along  the  sides.  The  larva  feeds  for  about  ten  days  and 
then  enters  the  soil  for  from  two  to  three  inches  and  there  con- 
structs a  small  oval  cocoon  about  one  third  inch  long,  which  looks 
like  a  pellet  of  earth,  being  formed  of  a  brown  mucilaginous  sub- 

*  Monophadnus  ruhi  Harris.  Family  Tenthredinidce.  See  V.  H.  Lowe, 
Bulletin  150,  N.  Y.  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  RASPBERRY  AND  BLACKBERRY    415 

r 

i 

stance,  interwoven  with  coarse  strands  of  silk,  to  which  particles  of 
earth  adhere.  The  larva  then  hibernates  until  the  next  spring, 
when  it  transforms  to  the  pupa  and  in  a  few  days  the  adult  ap- 
pears, usually  early  in  May. 

Control. — By   suddenly   jarring   or    shaking   the   bushes    the 
larvae  will  be  shaken  to  the  soil.     On  light  soils  this  habit  may 


Fig.  349. — The  raspberry  saw-fly  (Monophadnus  ruhi  Harr.) :  a,  male;  h, 
female;  c,  egg  blisters  on  leaf;  d,  larva;  e,  cocoons — all  much  enlarged. 
(After  Lowe.) 

be  utiHzed  for  their  destruction  by  jarring  them  to  the  ground 
and  following  with  cultivators  so  as  to  bury  the  larvae  in  the 
loose  soil.  This  will  be  particularly  applicable  in  hot  weather, 
if  the  soil  is  hot  and  dusty,  when  most  of  the  larvae  will  be  killed 
before  regaining  the  plants.  By  frequent  cultivation  in  late 
summer  or  fall  the  cocoons  might  be  brought  to  the  surface  and 
some  of  the  larvae  might  be  thus  killed  during  the  winter,  though 


416         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

this  needs  testing,  as  they  are  fairly  well  protected.  The  larvae 
may  be  readily  killed  with  arsenical  sprays,  and  if  arsenate  of 
lead  were  applied  at  the  rate  of  3  pounds  per  barrel  just  as  the 
plants  commence  to  flower,  it  would  undoubtedly  control  the 
pest  with  no  possibility  of  spotting  the  fruit,  or  Paris  green  with 
Bordeaux  mixture  might  be  used  in  the  same  way.  If  careful 
watch  is  kept  for  the  pest  it  can  probably  be  detected  in  time  to 
applj^  the  arsenicals,  which  will  be  much  the  easiest  and  most 
effective  to  use,  but  if  not  observed  until  the  canes  are  fruiting 
they  should  be  spraj^ed  with  hellebore,  1  ounce  to  1  gallon  of 
water.  Hellebore  may  be  dusted  on  the  plants  mixed  with  twice 
its  weight  of  flour,  but  the  spraying  may  be  done  more  thoroughly. 

The  Raspberry  Byturus  * 

The  Raspberry  Byturus  is  a  small  brown  beetle  belonging 
to  the  same  family  as  the  larde^  and  carpet  beetles,  most  of  which 
feed  on  animal  matter.  It  is  about  one-seventh  inch  long,  red- 
dish-yellow or  reddish-brown, 
and  covered  with  a  thick  coat 
of  pale,  tawny  hairs.  The 
beetles  appear  about  the  midde 
of  May  in  northern  Ohio.    They 

,     ,  ,      „    ,       feed  on  the  tender  foliage  and 
Fig.   350. — ^Larva   and   adult   of   the  ^  .  .in  i      i  i 

raspberry  byturus— enlarged.  (After     eat  mto  the  flower  buds,  and 
Goodwin.)  '  sometimes     emerge     in     such 

numbers  that  the  young  foliage  is  skeletonized  and  many  of  the 
flower  buds  do  not  develop.  Though  the  eggs  are  laid  in  June, 
they  have  not  been  observed.  The  larvae  appear  in  late  June  and 
July  and  feed  in  the  fleshy  head  on  which  the  berry  is  born,  caus- 
ing the  affected  berries  to  ripen  earlier,  making  them  small  and 
unfit  for  market.  Furthermore  the  little  larvae  not  infrequently 
remain  in  the  cup  of  the  berry,  which  necessitates  picking  the 
berries  over  and  injures  their  sale.  The  larva  is  about  one- 
quarter  inch  long,  rather  plump  and  cylindrical,  and  tapering 
at  each  end.  The  body  is  white,  but  each  segment  is  marked 
across  the  back  with  a  broad,  tawny  yellow  band,  and  numerous 

*  Byturus    unicolor    Say.     Family    DermestidcB.     See    W.    H.    Goodwin, 
Bulletin  202,  Ohio  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  RASPBERRY  AND  BLACKBERRY    417 


short  white  hairs.  When  full  grown  the  larva  drops  to  the 
ground  and  forms  an  earthen  cell  just  beneath  the  surface,  in 
which  it  transforms  to  a  yellowish  pupa,  from  which  the  beetle 
emerges  the  next  spring.  Only  red  raspberries  seem  to  be  affected, 
and  some  varieties  are  particularly  injured.     The  insect  has  been 


Fig.  351. — Early  ripening  berries,  the  smaller  ones  infested  with  Byturus 
larvae.     (After  Goodwin.) 

reported  as  injurious  from  Minnesota  to  Massachusetts  and  in 
Ontario. 

Control — Inasmuch  as  the  beetles  feed  freely  on  the  foliage 
before  o\apositing  they  may  be  destroyed  by  spraying  the  leaves 
with  arsenate  of  lead.  Mr.  Goodwin  has  shown  that  where 
foliage  was  sprayed  with  4  pounds  per  barrel,  that  three-fourths 
of  the  subsequent  injury  to  the  berries  by  the  larvae  was  pre- 
vented by  the  destruction  of  the  beetles,  and  the  injury  to  the 
flower  buds  was  also  lessened.  Thorough  cultivation  in  the  fall 
close  around  the  bushes  will  probably  destroy  many  of  the  pupae 
by  exposing  them  to  winter  weather. 


CHAPTER  XXII 
INSECTS  INJURIOUS  TO  THE  CURRANT  AND  GOOSEBERRY. 

The  Imported  Currant-borer  * 

One  of  the  worst  pests  of  the  currant  and  gooseberry  is  the 
borer,  v/hich  tunnels  out  the  canes  and  where  abundant  frequently 
kills  the  plants.     It  is  a  European  insect  which  has  spread  to 


Fig.  352. — The  imported  currant-borer  (Sesia  iipuliformis  Clerck):  moth, 
larva,  and  empty  pupal  skin  left  protruding  from  burrow.  (After 
Lugger.) 

all  parts  of  this  country  where  these  fruits  are  grown.     The 

adult  is  one  of  the  clear-winged  moths  and  with  the  larva  is  very 

similar  in  appearance  and   habits  to  the  raspberry  root-borer 

The  moth  is  about  one-half  inch  long  with  a  wing-expanse  of 

three-quarters  inch.     The  body  is  black  with  a  steel-blue  lustre, 

with  a  bright  yellow  band  around  the  neck  and  three  yellow 

bands  across  the  abdomen,  which  bears  a  large  tuft  of  long  scales 

at  the  tip.     The  wings  are  clear  except  for  a  margin  of  blackish 

scales  and  a  band  across  the  fore-wings  about  one-third  from 

the  tip. 

*  Sesia  tipuliformis  Clerck.     Family  Sesiidce.     See  Lugger,    1st  Report- 
Minn.  State  Entomologist,  p.  184. 

418 


INSECTS  INJURIOUS  TO  CURRANT  AND  GOOSEBERRY      419 

Life  History. — The  moths  appear  in  June  and  deposit  their 
small  globular,  brown  eggs  in  the  axils  of  the  leaves  next  the 
canes,  or  under  scales  or  in  cracks  of  the  canes.  The  young 
caterpillars  bore  into  the  pith  of  the  canes,  which  they  tunnel  out, 
and  are  about  half  grown  by  winter,  when  they  descend  to  the 
bottom  of  the  burrows  and  hibernate.  In  the  spring  they  con- 
tinue their  work  and  become  full  grown  by  May.  The  full- 
grown  larva  is  slightly  over  one-half  inch  long,  of  a  yellowish 
color,  with  brown  head,  and  with  numerous  small  tubercles  over 
the  body.  It  cuts  a  hole  through  the  side  of  the  burrow,  which 
it  closes  with  small  chippings,  and  then  transforms  to  the  pupa. 
When  the  moth  is  ready  to  emerge  the  pupa  wriggles  itself  partly 
out  of  the  burrow  by  means  of  the  strong  spines  on  the  abdomen, 
and  the  moth  comes  forth.  Affected  canes  can  be  recognized 
by  the  dwarfed  and  yellow  foliage  and  the  general  unhealthy 
appearance  of  the  plant,  and  if  not  removed  will  usually  die  during 
the  season. 

Control. — The  only  method  of  control  is  to  keep  all  the  old 
wood  removed  and  to  cut  out  and  burn  all  affected  canes  in  fall 
or  early  spring,  whenever  the  injury  may  best  be  detected. 

The  Currant-stem  Girdler  * 

In  late  spring,  after  the  young  currant-shoots  have  reached 
a  growth  of  several  inches,  two  or  three  inches  of  the  tips  some- 
times wilt,  and  fall  over  and  hang  suspended  or  drop  to  the  ground. 
If  examination  shows  that  the  tip  has  been  girdled  by  several 
sharp  cuts,  it  is  probably  the  work  of  the  Currant-stem  Girdler. 
It  is  a  native  insect  which  was  first  described  from  Massachusetts, 
and  has  also  been  found  injurious  in  Rhode  Island,  Canada,  Ohio 
and  Michigan,  but  has  been  most  troublesome  in  New  York. 
It  has  also  been  noted  as  a  pest  of  willow  and  poplar  in  Mary- 
land, and  of  basket  willow  in  Kentucky,  Indiana,  and  Ohio,  so 
that  it  is  doubtless  quite  generally  distributed.  The  adult  insect 
is  a  slender  saw-fly  with  shining  black  body  and  light  brownish 
legs,  shown  natural  size  in  Fig.  353a.  The  male  is  smaller  and 
has  a  brownish-yellow  abdomen,  while  in  the  female  the  first 

*  Janus  integer  l^orton.  Family  Tenthredinido'.  See  Slingerland,  Bul- 
letin 126,  Cornell  Univ.  Agr.  Exp.  Sta. ;  F.  H.  Chittenden,  Bulletin  No.  46, 
Bureau  of.  Forestry,  pp.  68-70. 


Fig.  353. — The  currant  stem-girdler  (Janus  integer  Norton):  a,  female  at 
work  girdling  a  currant  stem — natural  size;  b,  girdled  portion  of  stem 
much  enlarged  to  show  character  of  girdle;  c,  stem  cut  open  to  show 
egg;  d,  egg — much  enlarged.     (After  Slingerland.) 

420 


INSECTS  INJURIOUS  TO  CURRANT  AND  GOOSEBERRY   421 


half  of  the  abdomen  is  reddish-orange  and  the  rest  is  black.  The 
adults  are  abroad  in  May,  but  are  very  shy  and  are  seldom  seen. 
They  are  saw-flies  in  the  truest  sense  of  that  term,  for  the  female 
makes  most  effective  use  of  her  saw-like  ovipositor,  as  has  been 
very  interestingly  described  and  illustrated  by  Professor  Slinger- 
land.  The  ovipositor  is  thrust  into  the  cane  for  its  whole  length, 
and  through  it  the  egg  is  deposited  in  the  pith.  The  egg  is  an 
elongate-oval  shape,  yellowish-white,  and  about  one-twenty-fifth 
inch  long  (Fig.  353d).  Immediately  the  female  moves  an  inch 
or  two  higher  and  girdles 
the  stalk  by  numerous 
thrusts  of  her  ovipositor, 
which  is  thrust  in  and  then 
given  a  twist  to  one  side 
so  that  it  comes  out  at 
one  side  of  where  it  was 
forced  in,  and  makes  a  hori- 
zontal cut.  The  eggs  are 
laid  in  late  May  and  early 
June  and  hatch  in  about 
eleven  days.  The  young 
larvae  bore  into  the  pith,  but 
the  tunnel  rarel}^  extends 
over  six  inches  below  the 
point  girdled.  The  full- 
grown  larva  is  hardty  one- 
half  inch  long,  of  a  glistening  straw-yellow  color,  with  darker  head. 
The  thoracic  segments  are  wider  than  the  others  and  bear  rudimen- 
tary feet,  and  from  the  tip  of  the  stout,  cylindrical  abdomen  projects 
a  horny,  brown  bifid  spine.  In  the  fall  the  borer  cleans  out  its 
burrow  at  the  lower  end  and  eats  a  hole  through  the  woody  wall 
of  the  stem  to  the  outer  bark,  which  sinks  in  at  this  point.  The 
grub  then  spins  a  thin  silken  cocoon  about  itself,  in  which  it 
hibernates  over  winter,  transforming  to  a  whitish  pupa  in  April, 
from  which  the  adult  emerges  early  in  May.  The  girdling  of 
the  stalks  is  the  principal  injury,  and  those  which  harbor  the  pest 
may  be  recognized,  even  in  winter,  by  the  characteristic  dead 
stubs,  cut  off  squarely  at  the  upper  end. 


Fig.  354. — Currant  stem   girdled   by   the 
stem-girdler.     (After  SUngerland.) 


422         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Control. — The  drooping  of  the  tips  in  May  is  soon  noticed 
and  during  June  they  should  be  cut  off  about  three  inches  lower 
down  and  burned,  or  if  the  pruning  is  left  until  winter  the  infested 
stubs  should  be  cut  off  about  eight  inches  below  the  point  girdled, 
as  the  larvse  rarely  tunnel  deeper. 

The  Four-lined  Leaf-bug  * 

This  is  one  of  our  most  common  leaf-bugs,  which  has  a  long 
list  of  food  plants,  but  is  particularly  injurious  to  the  young 
fohage  of  currant  and  gooseberry.  The  adult  bug  is  easily 
recognized,  as  the  upper  surface  is  a 
dark  green  with  four  stripes  and  the 
tips  of  the  wing-covers  black,  as  shown 


Fig.  355. — The  four-lined  leaf -bug  (Pacilocapsus  lineatus  Fab.) :  a,  adult; 
h,  cross-section  of  stem  showing  eggs  in  position  and  a  single  egg  greatly 
enlarged.     (After  Slingerland.) 

in  Fig.  355.  The  green  changes  to  yellow  after  death  and  the  body 
is  bright  orange-yellow,  and  the  legs  green.  The  "presence  of  the 
pest  is  indicated  by  the  appearance  of  the  pecuhar  brown  depressed 
spots  on  the  tender  terminal  leaves"  in  early  summer.  "As  the 
attack  continues,  whole  leaves  turn  brown,  curl  up,  become  brittle, 
and  are  torn  or  broken  by  the  wind.  The  young  shoot  is  checked 
and  frequently  droops  and  dies.  The  buds  of  dahlias  and  roses  are 
often  blasted."  Slingerland  gives  a  list  of  some  fifty-seven  food- 
plants,  including  all  sorts  of  crops,  ornamental  plants  and  weeds. 

*  PoEcilocapsus   lineatus   Fab.     Family   Capsidoe.     See   Slingerland,    Bul- 
etin  58,  Cornell  Univ.  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  CURRANT  AND  GOOSEBERRY      423 


Parsnip,  mint,  sage,  rose,  deutzia,  dahlia,  and  others  are  often 
badly  injured.  The  species  has  been  observed  from  Canada  to 
Georgia  and  westward  to  the  Dakotas,  so  that  it  is  probably 
generally  distributed  east  of  the  Rockies. 

Life  History. — The  nymphs  hatch  from  the  overwintering  eggs 
in  late  May  and  early  June  and  are  very  largely  responsible 
for  the  injury  to  the  fohage.  The  newly  hatched  nymph  is  only 
about  one-twentieth 
inch  long,  but  is  easily 
recognized  by  the  shin- 
ing vermilion-red  color 
of  the  body,  marked 
with  large  blackish 
spots  on  the  thorax  and 
with  greenish-black 
antennae  and  legs.  The 
nymphs  grow  rapidly, 
becoming  full  grown  in 
seventeen  to  twenty 
days  after  hatching, 
during  which  time  they 
have  molted  five  times. 
The  full-grown  nymph 
is  about  one-fifth  inch 
long,  bright  orange 
yellow,  and  the  black 
wing-pads   extend  half 

way  to  the  end  of  the  Fig.  356. — Currant  leaf  spotted  by  the  nymphs 
,    ,  ,     ,  of  the  four-hned  leaf-bug.     (After  Shneerland.) 

abdomen   and    bear   a 

yellowish  green  stripe  near  the  outer  margin.     The  nymphs  feed 

on  the  tenderest  young  leaves,  sucking  out  the  juices  and  soft 

tissue  through  their  tiny  beaks,  and    thus    causing   the    spots 

mentioned.     "As  the  nymphs  increase  in  size  the  spots  are  a  little 

larger  and  more  numerous,  until  not  only  hundreds  occur  on  a 

single  leaf,  but  often  nearly  all  the  parenchyma  is   taken  from 

the  leaf."     The  nymphs  are  very  active  and  dart  from  one  side 

of  the  leaf  to  the  other  when  disturbed.     The  adult  bugs  appear 

about  the  middle  of  June  and  are  active  for  a  month  or  more,  when 

they  disappear.      They  mate  and  the  females  commence  to  lay 


424         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

eggs  about  a  week  after  they  first  appear.  The  female  is  furnished 
with  a  strong  ovipositor  with  which  she  inserts  the  eggs  in  slits  cut 
lengthwise  into  the  stems  of  the  plants  extending  nearly  half  way 
through  the  pith.  A  half-dozen  or  more  eggs  are  packed  together 
in  the  small  slit,  which  may  be  one-eighth  inch  long.  The  indi- 
vidual egg  is  about  one-sixteenth  inch  long,  hght  yellow,  and  shaped 
as  in  Fig.  355e,  with  the  upper  third  capped  by  a  white,  finely 
striated  portion.  "With  the  growth  of  the  surrounding  tissue  of 
the  stem,  the  eggs  are  usually  forced  out  of  the  slit  somewhat,  so 
that  about  one-half  ...  of  the  white  portion  of  the  egg  pro- 
jects from  the  slit."  Most  of  the  slits  are  made  two  or  three 
inches,  rarely  over  six  inches,  below  the  tender  tips. 

Cow^roZ.— Experiments    indicate    that    the    nymphs    may   be 


Fig.  357. — Currant  leaves  killed  by  the  four-lined  leaf-bug.     (After  Slinger- 

land.) 

killed  by  spraying  them  with  kerosene  emulsion  containing  10 
per  cent  kerosene.  Tobacco  extracts  should  also  be  tried.  The 
adults  are  not  susceptible  to  this  treatment,  however.  Both 
nymphs  and  adults  will  drop  from  the  foliage  when  disturbed, 
and  Professor  Slingerland  has  suggested  that  they  might  be  jarred 
into  a  pan  of  kerosene.  By  drawing  pans,  such  as  constructed 
for  combating  the  pea-aphis,  between  the  rows  and  jarring  the 
bugs  into  them,  many  might  be  destroyed.  As  the  eggs  are 
readily  recognized,  the  tips  containing  them  should  be  cut  off 
and  destroyed  during  the  winter. 


INSECTS  INJURIOUS  TO   CURRANT  AND  GOOSEBERRY      425 


The  Currant-aphis  * 

The  young  foliage  of  currants,  and  sometimes  of  gooseberries, 
is  often  found  curled  up  in  late  spring  with  many  bladder-Uke 
galls  on  the  leaves,  inside  of  which  are  found  the  numerous 
yellowish-green  plant-lice  which  have  caused  them.  The  wing- 
less females  are  about  one-twelfth  inch  long,  yellowish-green 
or  green,  mottled  with  darker  shades,  and  with  bright  red  eyes. 
The  winged  female  is  slightly  longer,  with  wings  expanding  one- 
third  inch.  It  is  bright  greenish-yellow,  with  pale  ohve  head, 
thoracic  lobes  brown,  and  the  abdomen  is  marked  by  several  dark 


Fig.  358. — Currant  foliage  curled  by  aphids.     (After  Lowe.) 

transverse   bands   and   lateral   spots.     It   is   an    old   European 

species  and  is  probably  found  throughout  the  United  States  where 

currants  are  grown. 

Life  History. — The  life  history  is  practically  the  same  as  that 

of  several  other  aphids  previously  described  and  need  not  be 

rehearsed  m  detail.     The  small  black  eggs  are  found  on  the 

stalks  in  winter  and  hatch  just  as  the  foliage  appears.     The  aphids 

multiply  on  the  fohage,  causing  it  to  curl  as  described,  until 

midsummer,  when  they  either  migrate  to  some  other  food-plant 

or  become  greatly  reduced  m  numbers  through  the  attacks  of 

parasites  and  predaceous  insects,  which  are  very  effective  in  the 

*  Myzus  ribis  Linn.  P'amily  Aphididoe.  See  V.  H.  Lowe,  Bulletin  139, 
N.  Y.  Agr  Exp.  Sta  ,  p.  660  Another  species,  Rhopalosiphum  ribis  Linn., 
is  also  common  on  currant  and  is  described  and  figured  by  Mr.  Lowe. 


426  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

control  of  this  species.  Mr.  Lowe  states  that  a  few  females  may 
be  found  on  the  foliage  throughout  the  summer.  In  late  October 
winged  males  appear  and  mate  with  the  true  females,  which  then 
lay  the  eggs. 

Control. — The  aphids  may  be  readily  killed  by  spraying  with 
kerosene  emulsion,  whale-oil  soap,  1  pound  to  6  gallons  of  water, 
or  tobacco  extracts,  but  the  spraying  must  be  done  before  the 


Fig.  359. — ^The  imported  currant-worm  (Pteronus  ribesii  Scop.):  a,  male  and 
female  saw-flies;  b,  larvae;  c,  pupa;  d,  cocoon;  e,  eggs — all  enlarged.  (After 
Lugger.) 

foUage   becomes   badly   curled.     Ordinarily   they   may   be   held 
in  check  by  picking  off  the  curled  leaves  by  hand. 

The  Imported  Currant-worm  * 

"  The  most  destructive  insect  that  attacks  the  currant,"  says 
Professor   Lugger,  "  is   the   above-named   saw-fly,    which   feeds 

*  Pteronus  ribeeii  Scpp.  Family  Tenthredinidce.  See  Lugger,  Bulletin 
'43  Minn.  Exp.  Agr.  Sta.,  179;  C.  L  Marlatt,  Bulletin  3,  T  ch.  Series, 
Div  Ent.,  p.  61. 


INSECTS  INJURIOUS  TO  CURRANT  AND  GOOSEBERRY      427 

indiscriminately  on  all  kinds  of  currants  and  gooseberries.  The 
imported  species  is  supposed  to  have  been  accidentally  introduced 
into  this  country  about  the  year  1857,  and  has  since  spread  over 
the  greater  part  of  the  United  States  and  Canada.  The  eggs  are 
glued  to  the  main-ribs  of  the  leaf  as  shown  in  Fig  359,  and  not 
inserted  into  pockets,  as  is  usually  the  case  with  saw-flies.  .  .  . 
In  from  four  to  ten  days  the  egg  hatches  into  a  very  small  whitish 
caterpillar  with  a  white  head  and  ornamented  with  black  spots 
on  each  side.  This  color,  however,  changes  to  green  as  soon  as 
the  caterpillars  begin  to  feed,  and  after  their  first  skin  is  shed, 
the  head  becomes  black  and  many  black  spots  appear  on  the  body. 
This  coloration  persists  until  the  last  molt  when  the  insect  becomes 
grass-green.  The  head,  however,  retains  the  black  spots  on 
each  side.  The  length  of  the  w^orm  is  now  about  three-fourths 
of  an  inch.  While  growing  they  at  first  skeletonize  the  leaves; 
later  they  eat  the  entire  leaf,  with  the  exception  of  the  ribs,  and  at 
last  they  devour  immense  quantities  of  them,  often  completely 
stripping  the  bushes  of  their  fohage.  If  this  is  repeated  year  after 
year,  the  plants  produce  less  and  less  fruit  and  eventually  die. 
The  larvse  now  descend  to  the  ground,  in  which  they  spin  a  small, 
oval  cocoon  of  brownish  silk,  either  just  below  the  surface  of 
the  ground  or  among  the  leaves  and  rubbish  that  collect  below  the 
plants.  Inside  these  cocoons  they  change  to  pupae  and  later 
to  adults,  which  are  ready  to  issue  as  winged  saw-flies  during  the 
last  of  June  or  in  July  (in  Minnesota),  sometimes  not  until  the 
first  of  August.  They  now  pair  and  produce  a  new  generation 
of  injurious  worms.  .  .,  the  adults  of  which  do  not,  however, 
issue  until  the  following  spring.  As  the  two  broods  overlap, 
we  can  find  larvse  of  all  stages  during  the  greater  part  of  the 
summer."  The  adult  saw-flies  are  well  illustrated  in  Fig.  359. 
The  female  is  about  one-third  inch  long,  of  a  light  yellowish  color 
marked  with  blackish  as  shown  in  the  figure,  while  the  male  is 
smaller  and  rather  darker. 
Control. — See  next  insect. 

The  Native  Currant-worm  * 

The  native  currant-worm  is  not  usually  so  destructive  as  the 
European   species,   but   occasionally,   becomes  injurious   and   is 

*  Gymnonychus  a-p-pendiculatus  Hartig.     Family  Tenthredinidce. 


428         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

widely  distributed,  occurring  from  New  England  to  Minnesota 
and  Colorado,  in  British  Columbia,  and  probably  in  the  Pacific 
States.  The  larva  is  about  two-thirds  the  size  of  the  imported 
species,  but  is  uniformly  pale-green  except  the  head  which  is 
black  until  the  last  molt,  after  which  it  becomes  partly  green. 
One  generation  of  larvae  appears  in  late  June  and  another  in 
August.  The  cocoons  are  usually  attached  to  the  twigs  or 
leaves  of  the  bushes.  The  female  saw-fly  is  dull  black  with  dull 
yellow  head,  and  honey-yellow  legs. 

Control. — While  fruiting  the  foliage  should  be  dusted  or  sprayed 
with  hellebore,  which  is  the  time-honored  remedy  for  currant- 
worms.  However,  before  the  fruit  has  set  and  after  it  is  picked, 
spraying  with  arsenicals  will  be  much  cheaper  and  more  effective, 
and  as  it  is  often  desirable  to  spray  gooseberries  for  diseases  with 
Bordeaux  mixture,  by  adding  arsenate  of  lead  or  Paris  green 
to  it,  the  worms  may  be  easily  controlled. 

The  Currant  Span-worm  * 

The  Currant  Span-worm  is  readily  distinguished  from  the 
other  cm-rant  "worms,"  by  being  one  of  the  measuring-worms 
or  inch-worms  which  loop  along  as  shown  in  Fig.  360.  It  is  not 
frequently  very  destructive,  but  occasionally  becomes  a  pest, 
more  particularly  of  black  currants  and  gooseberries,  throughout 
the  eastern  half  of  the  country.  The  caterpillar  is  sHghtly  over 
an  inch  long  when  full  grown,  and  of  a  whitish  color  with  a  wide 
yellow  stripe  down  the  back,  another  along  each  side,  and  several 
black  spots  on  each  segment.  The  under  side  is  white  with  a 
slight  pinkish  tinge,  with  a  broad  yellow  median  stripe,  and  is  also 
spotted  with  black.  The  moth  has  a  wing  expanse  of  about  1| 
inches,  is  a  pale  yellowish  color,  with  several  brownish  spots, 
varying  in  size  and  sometimes  forming  one  or  two  irregular  bands 
across  the  wings. 

Life  History. — The  eggs  (Fig.  360a)  are  laid  in  midsummer  on 
the  twigs  of  the  infested  plants  and  hatch  as  the  bushes  come 
into  full  leaf  the  next  spring.  The  caterpillars  become  full 
grown  in  three  or  four  weeks,  when  they  pupate  just  beneath 
the  surface  of  the  soil,  and  two  or  three  weeks  later  the  moths 
emerge. 

*  Cymatophora  ribearia  Fitch.    Family  Geometridce. 


INSECTS  INJURIOUS  TO  CURRANT  AND  GOOSEBERRY      429 

Control. — Hellebore  is  not  as  effective  as  against  the  saw-fly 
larvae  and  as  the  larvae  usually  appear  before  the  fruit  is  setting, 
they  may  be  better  controlled  by  spraying  with  arsenicals.  When 
the  caterpillars  are  disturbed  they  drop  from  the  foliage,  letting 
themselves  down  by  a  silken  thread  and  remaining  suspended  in 


Fig.  360. — The  currant  span-worm  {Cymatomorpha  riberia  Fitch):  1,  2,  larvae, 
3,  pupa;  a,  egg:;  b,  eggs  on  twig;  c,  moth — a,  much  enlarged,  others  natural 
size.     (After  Saunders.) 

mid-air  until  danger  is  over,  when  they  reascend  the  thread. 
This  habit  may  be  utilized  for  their  destruction  by  jarring  the 
bush  so  that  they  will  drop,  and  then  passing  a  forked  stick  around 
it  so  that  all  the  threads  may  be  caught  and  the  caterpillars  may 
be  drawn  out  in  groups  and  crushed  with  the  foot. 


The  Currant-fly  * 

Currants  and  gooseberries  sometimes  turn  red  and  drop  pre- 

maturety,  due  to  the  injury  by  small  maggots  which  may  be  found 

within  them.     The  insect  has  been  troublesome  in  Maine  and  is 

sometimes  a  serious  pest  in  Colorado.     It  is  a  native  insect  and  is 

probably  generally  distributed  throughout  the  northern  United 

States  and  southern  Canada.     The  adult  fly  is  about  the  size  of 

*  Epochra   canadensis    Loew.     Family    Trypetidce.     See    F.    L.    Harvey, 
Bulletin  35,  Maine  Agr.  Exp.  Sta. 


430  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

a  house-fly,  a  pale  yellowish  or  yellowish-brown  color,  with  dark 
bands  across  the  wings,  and  a  tapering  abdomen,  as  shown  in 
Fig.  361. 

Life  History. — The  flies  appear  in  late  spring  and  the  females 
deposit  their  eggs  in  the  older  berries.  A  female  will  lay  about 
200  eggs  during  the  period  of  a  month,  placing  but  one  in  a  berry, 
so  that  a  single  fly  may  do  considerable  damage.  The  white  egg 
is  about  one-twenty-fifth  inch  long  and  laid  just  under  the  skin, 
where  it  is  easily  seen.     The  egg  hatches  in  a  few  days  into  a 


Fig.    361. — The   currant-fly    (Epochra   canadensis   Loew.) — much    enlarged; 

(After  Gillette.) 

small  white  maggot,  which  burrows  around  the  berry  and  then 
feeds  upon  the  seeds.  The  location  of  the  larva  may  be  seen,  as 
the  infested  currant  soon  shows  a  clouded  appearance  and  finally 
turns  red  and  a  black  spot  appears.  The  maggot  becomes  full 
grown  in  about  three  weeks  and  then  eats  its  way  out  of  the  berry, 
which  has  usually  fallen  to  the  ground.  The  mature  maggot 
enters  the  soil  for  about  an  inch  and  there  changes  to  the  pupa, 
from  which  the  fly  emerges  the  next  spring. 

Control. — As  the  maggots  usually  remain  in  the  berries  a  few 
days   after  they  drop,   all  fallen   berries  should   be   frequently 


INSECTS  INJURIOUS  TO  CURRANT  AND  GOOSEBERRY    431 

picked  up  and  destroyed.  Poultry  running  among  the  bushes 
will  do  this  very  effectually.  Other  methods  will  suggest  them- 
selves from  the  above  life  history,  but  none  seems  to  have  been 
carefully  tested. 


CHAPTER  XXIII 

INSECTS  INJURIOUS  TO  THE  GRAPE.  * 


The  Grapevine  Phylloxera  f 

This  insect  is  native  east  of  the  Rocky  Mountains,  where  it 
has  always  lived  upon  wild  vines  and  did  not  attract  attention 
until  it  was  imported  into  France  about  1859,  as  it  does  prac- 
tically no  damage  to  the  native  American  grapes.  It  soon  spread 
through  the  principal  wine  districts  of  southern  Europe,  where  it 

caused  immense  losses  and 
the  temporary  abandon- 
ment of  vineyards,  due  to 
the  fact  that  the  European 
varieties  are  very  suscep- 
tible and  readily  succumb 
to  injury  by  it.  It  has 
spread  to  southern  Russia 
and  the  adjoining  count- 
ries of  Asia,  and  Algeria, 
and  has  been  carried  to 
New  Zealand  and  South 
Africa.  In  this  country 
it  is  injurious  only  in  Cal- 
ifornia, where  it  was  imported  on  French  vines  about  1874.  It 
was  first  noticed  in  Sonoma  County  and  since  then  has  spread  to 
all  the  principal  grape-growing  regions  north  of  Tehachapi  and  has 
probably  destroyed  50,000  acres. 

This  aphid  exists  in  several  forms,  which  injure  both  foliage 
and  roots.  On  the  leaves  irregular  spherical  galls  are  produced, 
and  the  root-inhabiting  form  produces  galls  on  the  roots.     The 

*  See  A.  L.  Quaintance,  Farmers'  Bulletin  284,  U.  S.  Dept.  Agr.  H  J. 
Quayle,  Bulletin  192,  Cal.  Agr.  Exp.  Sta.;  F.  Z.  Hartzell,  Bulletin  331,  N.  Y. 
Agr.  Exp.  Sta. 

t  Phylloxera  vastatrix  Planchon.  Family  A-phididce.  See  C.  L.  Marlatt, 
Farmers'  Bulletin  70,  U.  S.  Dept.  Agr.,  and  Quayle,  1.  c. 

432 


Fig.  362. — The  grapevine  phylloxera  (Phyl- 
loxera vastatrix  Planchon) :  a,  true  sexual 
female,  the  dark  colored  area  indicating 
the  single  egg;  b,  egg;  c,  shrivelled  female 
after  oviposition;  d,  foot  of  same;  e,  rud- 
imentary and  functionless  mouth-parts. 
(After  Marlatt,  U.  S.  Dept.  Agr.) 


INSECTS  INJURIOUS  TO  THE  GRAPE 


433 


leaf-galls  are  very  common  on  American  grapes,  but  are  no 
indication  of  the  presence  of  the  root  form,  as  the  roots  are  rarely 
injured  where  the  foliage  is  covered  with  leaf-galls.  On  the  other 
hand  the  European  varieties  rarely  exhibit  any  leaf-galls,  but  are 
very  susceptible  to  the  root  phylloxera,  which  multipUes  without 
any  external  indication  of  its  presence  until  the  vine  is  seriously 
injured.  The  injury  to  the  vine  is  not  due  so  much  to  the  sap 
taken  from  the  vine  by  the  myriads  of  aphids  which  may  inhal)it 
the  roots,  as  to  their  poisonous  effect  on  the  root  tissue  and  its 
subsequent  decay.  Wherever  the  phylloxera  attack  the  roots, 
small  swellings  are  pro- 
duced, composed  of  soft 
tissue  which  soon  decays. 
When  such  a  gall  is 
formed  at  the  end  of  a 
young  root,  its  growth  is 
stopped,  and  on  larger 
roots  a  decay  sets  in 
which  finally  girdles  the 
root  and  all  below  the 
injured  point  dies.  As 
all  the  roots  become 
affected  the  vine  stops 
growing,  the  leaves  be- 
come sickly  and  yellow- 
ish, and  the  vine  dies,  and 
the  phylloxera  disappears  from  the  rotting  roots,  so  that  the  cause 
of  the  injury  would  be  obscure  were  the  nature  of  the  injury  not 
known. 

Life  History. — The  life  history  of  the  phylloxera  is  a  com- 
phcated  one,  involving  four  different  forms  of  aphids;  the  leaf- 
gall  form,  the  root  or  destructive  form,  the  winged  or  colonizing 
form,  and  the  sexual  form.  The  winter  eggs  are  deposited  on  the 
rough  bark  of  the  old  wood  in  the  fall  and  hatch  the  following 
spring.  The  young  aphids  settle  on  the  leaves,  where  the  irrita- 
tion caused  by  their  mouth-parts  soon  causes  a  depression  around 
each  which  forms  a  gall  projecting  on  the  lower  side  of  the  leaf. 
"In  about  fifteen  days  the  louse  becomes  a  plump  orange-yellow, 
full-grown,  wingless  female,  and  fills  its  gall  with  small  yellow 


Fig.  363. — Under  side  of  grape  leaf  showing 
galls  caused  by  Phylloxera.    (After  Riley.) 


434 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


eggs,  dying  soon  after.  The  eggs  hatch  in  about  eight  days  into 
young  females  again,  like  the  parent,  and  migrate  to  all  parts  of 
the  vine  to  form  new  galls.  Six  or  seven  generations  of  these 
wingless  females  follow  one  another  throughout  the  summer, 
frequently  completely  studding  the  leaves  with  galls."  In  Cali- 
fornia the  young  hatching  from  the  winter  eggs  go  directly  to 
the  roots  where  they  give  rise  to  new  colonies,  there  being  no 
gall  forms,   according  to  Quayle.     Where  the  leaf-gall  females 


Fig.  364. — The  grapevine  phylloxera:  a,  winged  migrating  female;  h,  last 
stage  of  nymph  of  same;  c,  mouth-parts  with  thread-like  sucking  seta? 
removed  from  sheath;  d,  and  e,  eggs  of  male  and  female,  showing  sculp- 
turing— all  enlarged.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

occur  many  of  them  probably  migrate  to  the  roots  during  the 
summer,  and  all  do  so  with  the  approach  of  cold  weather.  In  the 
spring  the  roots  are  attacked  and  a  series  of  generations  of  wingless 
females  multiply  on  them.  As  there  are  five  to  seven  generations 
in  a  season  and  each  female  lays  from  30  (Quayle)  to  100  (Marlatt) 
eggs,  it  is  evident  that  they  will  soon  be  numerous  enough  to 
destroy  the  vine.  The  root-inhabiting  females  are  very  similar 
to  those  in  the  leaf -galls,  and  are  about  one-twenty-fifth  inch  long 
when  mature  and  half  as  long  when  young  and  active.  They  are 
light  greenish-yellow  in  summer  and  darker  in  winter,  and  when 
numerous  the  infested  roots  look  as  if  dusted  in  spots  with  pow- 


INSECTS  INJURIOUS  TO  THE  GRAPE 


435 


dered  mustard,  according  to  Quayle.  He  states  that  "the  newly 
hatched  insect  is  fairly  active,  and  at  first  moves  from  place  to 
place  on  the  roots,  but  finally,  when  it  reaches  the  egg-laying 
stage,  inserts  its  sucking-tube  into  the  root  and  remains  fixed." 
During  the  late  summer  and  early  fall  some  of  the  root-lice  develop 
into  winged  females  which  escape  through  cracks  in  the  soil  and 
fly  to  neighboring  vines.  They  lay  from  two  to  four  eggs  beneath 
the  loose  bark  on  the  old  wood  and  soon  die.  "The  eggs  are  of 
two  sizes,  the  smaller 
and  fewer  in  number 
yielding  males  in  nine 
or  ten  days,  and  the 
larger  the  females  of 
the  only  sexed  genera- 
tion in  the  whole  life 
round  of  the  insect. 
In  this  last  and  sexed 
stage  the  mouth-parts 
of  both  sexes  are  rudi- 
mentary, and  no  food 

at  all  is  taken.      The  Fig.  365.— Grapevine  phylloxera:  a,  root  galls; 

insect  is  very  minute  h  enlargement  of  same  showing  disposition 

"^  oi  lice;    c,  root-gall  louse  —  much  enlarged. 

and    resembles    the  (After  Marlatt,  U.  S.  Dept.  Agr.) 

newly  hatched  louse  of  either  the  gall  or  root  form.  After  fertili- 
zation the  single  egg  of  the  larva-hke  female  rapidly  increases 
in  size  until  it  fills  the  entire  body  of  the  mother  and  is  laid  within 
three  or  four  days,  bringing  us  back  to  the  starting  point."  * 
The  phylloxera  has  been  distributed  over  the  world  by  infested 
rooted  plants  or  cuttings  bearing  winter  eggs,  and  it  spreads 
locally  by  means  of  the  winged  females,  by  the  escape  of  the 
young  root-lice  through  cracks  of  the  soil  and  their  migration 
to  neighboring  plants,  or  by  bits  of  infested  roots  being  spread 
in  cultivation,  and  by  the  leaf-gall  lice  being  spread  to  other 
plants  by  the  wind  or  by  being  carried  by  birds  or  insects. 

Control. — The  principal  means  of  control  lies  in  the  use  of 
resistant  vines.  These  may  be  varieties  which  have  proven 
successful  in  the  eastern  United  States,  where  the  insect  is  native, 
or  more  commonly  the  stocks  of  grapes  from  the  Eastern  States 

*  Quotations  from  Marlatt,  1.  c. 


436  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

are  grafted  with  the  desired  varieties.  There  is  a  marked  varia- 
tion in  the  resistance  of  different  species  and  varieties  and  not  all 
of  them  can  be  successfully  used  as  stocks  for  the  desired  scions, 
so  that  the  successful  use  of  the  method,  which  is  fully  outHned 
by  Quayle,  I.e.,  requires  a  considerable  knowledge  of  viticulture. 

Carbon  bisulfide  has  been  used  very  extensively  for  destroying 
the  root-Hce,  but  is  expensive  and  is  only  applicable  on  rich,  deep, 
loose  soils.  It  cannot  be  used  successfully  on  soils  containing 
much  clay,  or  on  dry  rocky  hillsides,  or  when  the  soil  is  saturated 
with  moisture,  and  is  most  effective  on  sandy  soils  where  the 
insect  is  least  injurious.  It  is  now  seldom  used  and  is  considered 
impractical  by  growers. 

One  of  the  best  methods  of  destroying  the  root-lice  where 
water  is  available  is  by  submersion.  In  California  the  best  results 
are  secured  by  flooding  with  at  least  six  inches  of  water  for  a 
week  or  ten  days  as  soon  as  the  vines  have  ceased  active  growth 
in  November.  A  little  later  two  to  three  weeks'  submersion  will 
be  necessary  and  in  winter  thirty-five  to  forty  days.  Flooding 
for  a  couple  of  days  in  midsummer  seems  to  destroy  some  of  the 
insects,  but  its  main  value  is  in  stimulating  a  vigorous  growth 
of  new  rootlets.  Longer  flooding  in  summer,  when  the  aphids 
might  be  most  easily  destroyed,  injures  the  vines. 

On  very  sandy  soils  vines  are  uninjured  by  the  phylloxera. 
All  sandy  soils  are  unfavorable  to  the  pest  and  vines  on  them  die 
more  slowly,  but  to  secure  complete  immunity  there  must  be  at 
least  60  per  cent  of  siUcious  sand.  Sands  containing  clay  or 
which  form  lumps  offer  less  resistance. 

The  Grapevine  Root-borer  * 

The  larvae  of  the  Grapevine  Root-borer  feed  in  the  old  roots  at 

some  httle  distance  from  the  base  of  the  vine,  and  as  there  are 

no  indications  of  the  pest,  its  presence  may  easily  pass  unnoticed. 

Although  not  generally  recognized  as  a  serious  one  it  has  been 

known  as  a  pest  of  the  grape  for  fifty  years,  and  has  been  observed 

to   do   considerable   damage   in   Kentucky   and   West   Virginia. 

Although  the  vines  are  not  killed,  they  are  so  enfeebled  that  they 

make  but  little  growth  and  the  crop  is  much  curtailed.     All 

*  Memythrus  polistiformis  Harris.  Family  Sesiidce.  See  Fred  E.  Brooks, 
Bulletin  110,  W.  Va.  Agr.  Exp.  Sta.,  and  Bulletin  730,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  THE  GRAPE 


437 


varieties  are  affected  in  West  Virginia,  including  the  wild  fox 
grape,  Vitis  labrusca.  It  is  stated  that  in  the  South  the  Scupper- 
nong,  or  southern  wild  fox  grape,  is  immune  from  attack.  The 
species  has  been  observed  from  Minnesota  and  Kansas  eastward 
through  Ohio  and  Kentucky  to  West  Virginia  and  North  Carolina. 
The    parents   of  the   borers  are   clear-winged   moths   nearly 


Fig.  366. — The  grapevine  root-borer  (Memythrus  polistiformis  Harris) :  male 
and  female  moths  on  wild  lettuce  leaf  under  grapevine — natural  size. 
(From  Brooks.) 

related  to  the  peach-tree  borer,  currant-borer,  and  raspberry- 
borer.  The  females  are  seven-eighths  inch  long  with  wings  expand- 
ing 1^  inches.  They  are  a  dark  lustrous  brown  color,  the  fore- 
wings  being  brown  and  the  hind-wings  transparent  and  bordered 
with  brown.  The  posterior  margins  of  the  second  and  fourth 
abdominal  segments  are  orange  or  lemon-yellow,  and  there  are 
spots  of  the  same  color  at  the  bases  of  the  wings.     The  males 


438         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

are  considerably  smaller  than  the  females.     The  moths  fly  during 

the  day  and  are  readily  mistaken  for  wasps  of  the  genus  Pohstes. 

The  males  fly  in  a  quick,  wasp-like  manner,  and  when  they  rest 

on  a  leaf  will  occasionally  flutter  the  wings  hke  an  angry  wasp, 

which  is  accompanied  by  a  low  buzzing  sound,  which  makes  the 

mimicry  very  effective. 

Life  History. — The  eggs  are  laid  singly  on  weeds,  grasses  or 

other  vegetation  in  the  vineyard  or  on  the  bark  or  leaves  of  the 

vines,  a  single  female  laying  some  400  eggs. 

The  egg  is  oval,  one-twenty-fifth  inch  long, 

of   chocolate-brown   color,   and   finely   pitted 

and  sculptured.     They  are  very  readily  washed 

off  by  the  rain  and  drop  to  the  soil,  where 

they  hatch  in  about  three  weeks.     The  httle 

larvae   bore  directly  into  the   soil,   wherever 

Fig.  367.— Egg    of     ^j^ey  may  be,  in  search  of  grape  roots,  and 
grapevine      root-  •         <-  i     i  -.i        - 

borer  — v  e  r  y     may   survive  for  several   days   without   any 

greatly  enlarged,  food.  Upon  reaching  a  root  the  larva  bores 
through  the  outer  bark  and  then  makes  an 
irregular  burrow  in  the  softer  parts  of  the  bark,  which  may 
encircle  the  root  several  times.  As  the  burrows  grow  larger 
they  run  with  the  grain  of  the  wood,  and  as  they  are  enlarg- 
ed with  the  growth  of  the  larva,  only  the  outer  bark  is  left 
on  roots  one-half  inch  or  less  in  diameter,  the  interior  being 
tunnelled  out  and  filled  with  the  castings  of  the  larva.  Most 
of  the  larvae  feed  a  foot  or  so  from  the  base  of  the  vine,  though  one 
was  found  on  a  root  nine  feet  from  the  base.  The  larvse  bore  in 
the  roots  until  the  second  fall,  when  they  are  about  full  grown  and 
make  cells  or  hibernacula,  thinly  lined  with  silk,  in  which  they 
hibernate  in  the  root.  The  larva  becomes  full  grown  the  next 
spring  and  is  then  1|  to  If  inches  long,  of  the  general  shape 
shown  in  Fig.  368,  yellowish-white,  with  a  small  brown  head,  three 
pairs  of  brown  thoracic  legs,  and  five  pairs  of  abdominal  prolegs. 
When  ready  to  pupate  the  larva  comes  near  the  surface  of  the 
soil  and  there  makes  a  tough  cocoon  an  inch  or  so  long,  composed 
of  earth  and  excrement  and  fined  with  silk,  and  in  it  transforms 
to  a  brown  pupa  with  yellow  bands  around  the  abdomen.  In 
about  four  or  five  weeks  the  pupa  wriggles  half  way  out  of  the 
cocoon  and  the  moth  emerges,   leaving  the  empty  pupal  skin 


INSECTS  INJURIOUS  TO  THE  GRAPE 


439 


projecting  above  tlu^  surface  of  the  ground.     The  moths  emerge 

in  late  July  and  early  August  in  West  Virginia  and   the  eggs  are 

laid  in  a  few  days,      ^r 

Thus  the  life  cycle 

requires    two    full 

years  and  larvae  of 

two   sizes   may  be 

found  in  the  roots 

at  any  time,  except 

during    the     pupal 

period,  when  all  will 

be    about    half    to 

two-thirds    grown. 

Control. — On  ac-  i 
count  of  their  sub- 
terranean habits  it 
is  manifestly  im- 
possible to  dig  out 
the  borers,  as  is  done 
with  similar  species 
except  for  a  few 
valuable  vines.  If 
the  Scuppernong  is 
as  immune  as  has 
been  reported,  it 
might  be  used  as 
a  stock  throughout 
the  South,  where  it 
will  thrive.  By 
recognizing  the  par- 
ent moths,  they 
may  be  destroyed  by  approaching  them  quietly  when  at  rest  and 
striking  them  quickly  with  a  paddle  or  board  and  many  might  thus 
be  killed  during  the  time  they  are  most  abundant. 

By  thorough  cultivation  in  June  and  July  many  of  the  cocoons 
will  be  thrown  to  the  surface  or  buried  so  deeply  that  many  of 
the  pupae  will  be  destroyed,  or  the  adults  will  be  unable  to  reach 
the  surface.  With  liberal  fertiUzation,  cultivation  will  stimu- 
late the  vine  to  withstand  the  injury.  Brooks  has  shown  that 
in   West   Virginia   the    crested    flycatcher    (Myiarchus  crinitus) 


Fir,.  ,368. — Grapevine  root-borers  at  work.  Five 
borers  were  feeding  in  this  section  when  taken  from 
the  ground — two-thirds  natural  size.  (Photo  by 
W.  E.  Rumsey.) 


--.^ 

fsgK^KK^B^' 

\ 

_^ 

^'^^^^^^^ 

s 

^■^x^' 

W'y       ^ 

-^ 

t\ 

t^tMtJtr              -^^P 

<i 

^Hp' 

^ 

.'>!"■.  ', 

"ii*  •-         *■-  ■'•'?■  !t 


Fig.  369. — Grape    root-worm    {Fidia    v'dicida  Walsh):     beetles    feeding    on 
foliage — natural  size,  and  enlarged.     (After  Slingerland.) 

440 


INSECTS  INJURIOUS  TO  THE  GRAPE  441 

feeds  upon  the  moths  and  may  be  a  factor  in  the  control  of  the 
pest 

The  Grape  Root-worm  * 

The  Grape  Root-worm  is  the  larva  of  a  small,  hairy,  chestnut- 
brown  beetle  which  feeds  on  the  upper  surfaces  of  the  leaves 


Fig.  370. — ^The  life  cycle  of  the  grape  root-worm — enlarged  and  natural  size. 
(After  Slingerland.) 

eating  out  series  of  patches  or  holes  in  characteristic  chain-like 
feeding  marks  which  afford  an  easily  recognizable  indication  of  the 

*  Fidia  viticida  Walsh.  Family  Chrysomelidce.  See  Quaintance,  I.e.; 
Hartzell,  I.e.,  and  Bulletin  453,  N.  Y.  Agr.  Exp.  Sta.;  M.  V.  Slingerland, 
Bulletins  184,  208,  224,  and  235,  Cornell  Univ.  Agr.  Exp.  Sta.;  E.  P.  Felt, 
Bulletin  19,  Office  State  Ent.  of  N.  Y.;  Fred  Johnson,  Bulletin  68,  Part  VI, 
Bureau  Entomology,  U.  S.  Dept.  Agr.;  Johnson  and  Hammar,  Bulletin  89, 
ibid. 


442         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


presence  of  the  pest  in  the  vineyard.  The  larvae  devour  the  smaller 
roots  and  eat  out  pits  and  burrows  in  the  larger  roots,  and  where 
abundant  may  kill  the  plants  in  a  year  or  two,  but  more  commonly 
they  cause  an  enfeebled  growth  and  a  consequent  failure  to  produce 
profitable  crops.  Injury  has  been  most  severe  in  the  grape  belt 
of  western  New  York,  Pennsylvania,  and  northern  Ohio,  but  the 
species  occurs  generally  throughout  the  Mississippi  Valley  and 


Fia.  371. — Eggs  of  the  grape  root-worm,  natural  size  as  seen  on  grape  canes 
above — enlarged  below.     (After  Slingerland.) 

the  Eastern  States,  and  has  been  reported  from  California.  "The 
insect  thrives  best  in  vineyards  which  are  neglected,  and  in  the 
absence  of  cultivation  and  timely  spraying  it  is  likely  to  become 
a  serious  pest  in  any  vineyard  throughout  its  range  of  d'stribu- 
tion.  This  is  especially  the  case  in  light,  sandy  soils  and  in  regions 
where  grape  growing  is  a  considerable  industry."  A  nearly 
related  species,*  has  been  known  to  injure  the  foliage  seriously 
*  Fidia  cana. 


INSECTS  INJURIOUS  TO  THE  GRAPE 


443 


in  Texas,  but  it  is  not  known  whether  it  affects  the  roots.  In 
California,  the  imported  grape  root-worm  *  is  sometimes  destruc- 
tive, has  practically  identical  habits,  and  is  controlled  by  the 
same  methods. 

The  adult  beetle  is  about  one-quarter  inch  long,  brownish  in 
color,  and  covered  with  grayish-white  hairs,  with  a  stout  body 
and  long  legs,  as  shown  in  Fig.  369.  The  full-grown  larva  is 
about  five-eighths  inch  long,  whitish  in  color,  and  usually  rests 
in  a  curved  position  as  shown  in  Fig.  370.     The  head  is  shghtly 


372. — Portions  of  three  grape  roots  denuded  of  their  bark  and  fibrous 
roots  by  grape  root-worms,  and  part  of  a  similar  root  taken  from  a 
thrifty  vine,  showing  its  normal  bark  and  rootlets.  Reduced  in  size. 
(After  Slingerland.) 

narrower  than  the  body  and  j^ellowish-brown,  as  are  the  well- 
marked  spiracles  on  the  side  of  each  segment. 

Life  History. — The  adult  beetles  appear  about  the  close  of  the 
blooming  period,  or  in  late  June  and  early  July  in  the  latitude 
of  New  York,  and  live  for  a  month  or  more.  They  emerge  earlier 
on  warm,  Ught  sandy  soils,  and  later  on  heavier  soils.     In  a  few 

*  Adoxus  vitis  Fourcroy.  A  small,  shining,  brown  or  black  beetle,  one- 
fifth  inch  long.     See  Quayle,  I.e. 


444      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


days  their  feeding  commences  to  be  noticed  on  the  leaves  and  the 
females  may  be  found  laying  their  eggs.  A  female  will  lay  from 
150  to  900  eggs,  averaging  about  175,  most  of  which  are  laid 
during  the  first  two  or  three  weeks.  The  eggs  are  laid  in  masses 
of  25  to  40  beneath  the  old  bark  or  generally  over  the  canes. 
The  individual  egg  is  one-twenty-fifth  inch  long,  at  first  whitish, 
but  soon  turns  yellow,  and  tapers  at  each  end.  The  eggs  hatch 
in  from  nine  to  twelve  days,  when  the  young  larvse  drop  to  the 
ground  and  seek  the  roots.  The  young  larvae  are  only  one- 
seventeenth  inch  long,  so  that  they  are  able  to  penetrate  the  soil. 
When  established  on  the  roots  they  feed  freely  and  grow  rapidly, 


Fig. 


373. — 1'he  tender  pupa  of  tin'  ^rape  root-worm  in  its  earthen  cell, 
enlarged — natural  size  at  n.     (After  Slingerland.) 


becoming  nearly  full  grown  by  fall.  In  the  fall  they  descend 
several  inches  into  the  soil  and  make  small  earthen  cells,  in  which 
they  hibernate.  In  the  spring  they  return  to  the  roots  nearer 
the  surface,  and  those  not  already  full  grown  feed  until  growth 
is  completed.  They  then  make  small  earthen  cells  2  or  3  inches 
below  the  surface  of  the  ground  in  which  they  transform  to  pupae. 
These  cells  are  easily  broken  open  and  the  pupse  are  thus  crushed 
or  killed  by  stirring  the  soil  in  cultivation.  The  pupa,  shown 
in  Fig.  373e,  is  one-quarter  to  one-third  inch  long,  whitish,  with 
the  head,  thorax  and  tip  of  the  abdomen  pinkish,  and  with  spines 
on  the  head,  appendages,  and  abdomen  as  illustrated.  The  pupse 
are  most  abundant  in  New  York  during  June,  the  pupal  stage 
lasting  about  two  weeks. 


INSECTS  INJURIOUS  TO  THE  GRAPE 


445 


Control. — Extensive  experiments  made  by  several  investigators 
have  shown  that  the  beetles  may  be  very  largely  destroyed  by 
thorough  spraying  with  arsenate  of  lead  just  as  they  appear. 
By  applying  the  poison  when  they  are  first  noticed  feeding  they 
may  be  killed  off  before  many  of  the  eggs  are  laid,  and  sprayed 
vineyards  have  shown  a  reduction  of  over  90  per  cent  of  the  eggs 
found  on  untreated  vines.  Arsenate  of  lead  should  be  applied  at 
the  rate  of  3  pounds  to  the  barrel  as  soon  as  feeding  marks  are 
found  on  the  foliage,  and  again  a  week  or  ten  days  later,  and 
should  be  added  to  the  Bordeaux  mixture  used  for  the  diseases 
of  the  vine.  The  spraying  must  be  done  with  the  greatest  thor- 
oughness, as  the  beetles  dislike  the  spraj^ed  foliage  and  will  seek 
out  that  which  has  been 
missed.  The  nozzles  on  trac- 
tion outfits  should  therefore 
be  arranged  so  as  to  hit  all 
parts  of  the  vines  (see  Fig. 
374)  and  the  pump  should 
maintain  at  least  100  pounds 
pressure.  With  the  machines 
in  common  use  not  over  7  or  8 
acres  a  day  may  be  covered 
thoroughly,  and  about  125 
gallons  will  be  required  per 
acre.  If  the  work  is  hurried 
to  cover  greater  acreage,  the  treatment  will  usually  be  less  effec- 
tive. When  the  infestation  is  unusually  severe  cheap  molasses 
may  be  added  to  the  arsenate  spray  to  make  it  attractive  to  the 
beetles. 

The  beetle  is  noticeably  less  destructive  in  well-cultivated 
vineyards,  and  it  has  been  shown  that  thorough  cultivation  in 
early  summer  breaks  up  the  pupal  cells  and  destroys  large  num- 
bers of  the  pupse.  Most  of  the  pupae  are  within  2  or  3  inches 
of  the  surface  and  within  1|  or  2  feet  from  the  base  of  the  vine. 
In  the  fall  the  earth  should  be  thrown  toward  the  vines  to  form 
a  ridge  along  the  row,  so  that  the  larvae  will  mostly  pupate  near 
the  surface  of  this  ridge.  The  next  spring,  when  most  of  the 
larvae  have  entered  the  pupal  stage,  this  ridge  should  be  thrown 
away  from  the  vines,  thus  exposing  the  pupae.     A  "horse-hoe" 


Fig.  374. — A  power  sprayer  with  noz- 
zles arranged  for  grape  spraying  (The 
Bean  Spray  Pump  Co.) 


446      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


commonly  used  in  vineyards  is  useful  in  this  work,  but  a  hand- 
hoe  will  need  to  be  used  to  throw  the  earth  away  from  the  imme- 
diate base  of  the  vine.  The  soil  should  then  be  kept  well  stirred 
by  cultivation  at  frequent  intervals,  all  of  which  is  merely  part 
of  good  practice,  independent  of  the  control  of  the  root-worm. 

The  Grapecane  Gall-maker  * 

The  Grapecane  Gall-maker  is  a  small  reddish-brown  snout- 
beetle  about  one-eighth  inch  long,  which  lays  its  eggs  in  the 

canes,  giving 
rise  to  galls 
about  twice  the 
diameter  of  the 
cane  and  1  or 
1|  inches  long, 
with  a  deep  scar 
in  one  side.  It 
has  been  noted 
as  injurious  in 
Ohio  and  West 
Virginia,  and 
fromtherecords 
seems  to  be  gen- 
erally distrib- 
uted over  the  Eastern  States,  but  is  by  no  means  a 
serious  pest. 

Life  History. — The  adult  beetles  appear  in  May 
and  are  gone  by  early  July.  They  feed  sparingly 
on  the  vine,  making  little  pits  in  the  tendrils,  in  the 
buds  or  bark  of  new  canes  or  in  the  midribs  on  the 
under  side  of  the  leaves.  The  females  soon  lay  their 
eggs  and  make  the  egg  scars.     These  cause  the  galls 

Fig.  375. — The  grapecane  gall-maker  (Ampelogbjpter  sesostris  Lee):  a,  adult 
from  above;  b,  same,  side  view;  c,  larva,  side  view;  d,  pupa;  e,  section 
of  vine  showing  galls — all  enlarged.  (After  F.  M.  Webster.)  Natural 
size.     (After  Brooks.) 

*  Ampelnglypter  sesosiris  Lee.  Family  Ctirculionidoe.  See  Fred  E.  Brooks, 
Bulletin  119,  W.  Va.  Agr.  Exp.  Sta..;  F.  M  Webster,  Bulletin  116,  Ohio 
Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  THE  GRAPE  447 

and  constitute  practically  the  only  injury  to  the  vine.  The  eggs  are 
laid  just  above  a  joint  and  beyond  the  outermost  fruit,  so  that  the 
injury  does  not  interfere  with  the  crop.  A  female  eats  out  a 
small  hole  with  her  snout,  in  it  lays  a  small  yellowish-white  egg, 
and  fills  up  the  hole  with  fibers  scraped  off  from  the  surface  of 
the  cane.  She  then  makes  another  hole  immediately  above  this, 
but  merely  places  a  drop  of  liquid  in  it  and  then  fills  it  up  with 
fibers  in  the  same  manner.  Eight  to  a  dozen  holes  are  thus  made 
in  a  row  and  filled.  Very  soon  this  wound  causes  a  swelling  of 
the  vine,  but  the  gall  does  not  reach  full  size  for  six  or  eight  weeks. 
On  vines  producing  dark-colored  fruit,  the  wood  about  the  wound 
takes  on  a  purplish  color.  The  galls  seem  to  have  but  little  effect 
on  the  growth  and  vigor  of  the  vine,  except  that  the  canes  are 
more  readily  broken  by  the  wind  or  in  pruning.  The  larva  is  a 
little  yellowish-white,  footless  grub  about  two-fifths  inch  long, 
which  feeds  about  the  egg-chamber  and  then  burrows  in  the  pith. 
It  becomes  full  grown  in  eight  to  ten  weeks,  when  it  pupates 
within  the  burrow;  the  beetle  emerges  in  late  August,  and 
hibernates  over  winter. 

As  the  scar  in  the  side  of  the  gall  where  the  eggs  were  deposited 
remains  open,  a  very  large  proportion  of  the  larvae  are  subse- 
quently parasitized  by  various  chalcis,  and  tachina-flies,  which 
will  probably  prevent  the  insect  ever  becoming  much  of  a  pest. 

Control. — The  galls  may  be  cut  out  and  burned  during  July 
or  August  without  any  injury  to  the  crop,  as  they  occur  beyond 
the  fruit,  and  at  that  time  will  contain  the  larvae  or  pupae.  As 
the  beetles  feed  on  the  foliage  and  new  growth  it  is  probable 
that  but  little  damage  will  result  in  vineyards  well  sprayed  with 
arsenicals  for  other  pests. 

The  Grapecane  Girdler  * 

This  beetle  is  very  similar  to  the  last  except  that  it  is  black 
in  color.  Its  native  food-plant  is  the  Virginia  creeper,  which 
it  has  deserted  in  West  Virginia,  and  occasionally  elsewhere, 
to  attack  grape.  The  species  seems  to  occur  generally  through 
the  Central  and  Eastern  States. 

*  A7npelogh/pter  ater  Lee.  Family  Curculionidoc.  See  Fred  E,  Brooks, 
Bulletin  119,  W.  Va.  Agr.  Exp.  Sta. 


448      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Life  History. — The  life  history  is  almost  identical  with  that 
of  the  preceding  species,  the  habit  of  the  species  differing  only 
in  the  manner  of  oviposition.  The  eggs  are  laid  in  late  May  and 
early  June.  In  laying  the  egg,  the  female  deposits  it  in  the  same 
manner  as  does  the  previous  species,  and  then  instead  of  placing 
a  series  of  holes  in  a  row  she  makes  them  in  a  ring  around  the 
cane,  only  the  first  one  containing  an  egg.  She  then  goes  to 
the  next  joint  above  and  makes  a  series  of  holes  around  it,  com- 
pletely severing  it,  so  that  it  hangs  by  a  shred  and  soon  drops. 
The  httle  larva  feeds  in  the  pith  of  the  joints  on  either  side  of 
the  egg  puncture,  and  these  two  joints  die  and  drop  to  the  ground. 
The  larva  becomes  full  grown  in  about  a  month  and  changes  to 


Fig.  376. — The  grapecane  girdler  (Atnpeloglypter  ater  Lee):  a,  egg;  b,  larva; 
c,  pupa;  d,  beetle — all  enlarged.     (After  Brooks.) 

a  pupa  in  its  burrows  soon  after  the  dead  section  drops,  first 
filUng  the  burrow  with  little  pellets  of  fibres.  Two  weeks  later 
the  adult  beetle  emerges,  appearing  during  late  summer.  The 
whole  life  cycle  thus  requires  sixty-five  to  seventy  days.  The 
beetles  hibernate  over  winter. 

Control. — The  injured  canes  are  quite  conspicuous  in  early 
summer  and  by  cutting  them  off  a  few  inches  below  the  egg  scars 
the  eggs  and  larvae  may  be  removed  and  destroyed.  Brooks  is 
of  the  opinion  that  the  beetles  will  be  largely  destroyed  in  vine- 
yards thoroughly  sprayed  with  arsenicals  for  other  grape  insects. 


INSECTS  INJURIOUS  TO  THE  GRAPE 


449 


The  Grape  Cane-borer  * 
During  the  spring  young  grape  shoots  sometimes  suddenly 


%^ 


I 


Fig.  377. 


break  off  or  droop  and  die,  and 
if  examined  a  small  hole  will 
be  found  just  above  the  base 
of  the  withered  shoot,  with  a 
burrow    leading  from  it  into 
the  main  stem.     In  this  bur- 
row  will    be    found    a    small 
brown  beetle,  a  half  inch  long 
(Fig.  378a),  which  is  the  cause 
of   the   injury.      It  has  been 
y     sometimes    called    the    apple 
*     twug-borer  on  account  of  the 
J     similar  injury  which  it  does  to 
apple    twigs,     and    it    also 
.     attacks    pear,     peach,    plum, 
,  >     forest   and    shade    trees    and 
■  :^     ornamental  shrubs,  but  it   is 

Work  of  the  grapecane  girdler.     (After  Brooks.) 

See   C.   L.   Marlatt, 


*  Amphicerus   hicmidatus   Say.     Family   Ptinidce. 
Farmers'  Bulletin  70,  U.  S.  Dept.  Agr. 


450         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


particularly  destructive  to  the  grape.  Its  injury  is  most  noticed 
in  winter  and  early  spring,  and  frequently  results  in  killing  all 
the  new  growth  and  sometimes  the  entire  vine.  Injury  has  been 
most  severe  in  the  states  bordering  the  Mississippi  from  Iowa 
southward,  where  it  is  one  of  the  most  serious  insect  pests  of 
the  vine,  and  though  the  beetle  occurs  eastward  to  the  coast  it 
rarely  does  much  damage  farther  east. 


f^     A 


x:::^^ 


(y    uc:-^ 


Fig.  378. — The  grape  i^ane-borer  (Amphicems  hicaudatus  Say):  a,  beetle, 
back  and  side  views;  h,  pupa;  c,  larva,  with  feet  enlarged;  d,  burrow  in 
apple  twig  made  by  adult;  e,  larval  gallery  in  tamarisk,  with  pupa  in 
cell  at  end;  /,  injury  to  young  shoots  and  cane  showing  entrance  of  beetle 
near/,  and  the  characteristic  wilting  and  new  growth — all  much  enlarged 
except  d,  e,  f.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

"It  breeds  in  dying  wood,  such  as  large  prunings,  diseased 
canes,  and  also  in  dying  or  drying  wood  of  most  shade  and  fruit 
trees.     It  has  also  been  found  by  the  writer  [Marlatt]  breeding 


INSECTS  INJURIOUS  TO  THE  GRAPE  451 

very  abundantly  in  roots  of  uprooted  maples  and  in  diseased 
tamarisk  stems.  In  old,  dry  wood  it  will  not  breed,  so  far  as 
known,  nor  in  vigorous  live  growth,  but  seems  to  need  the  dying 
and  partially  drying  conditions  mentioned.  The  insect  has  but 
one  brood  yearly.  The  beetles  mature  for  the  most  part  in  the 
fall,  and  generally  remain  in  their  larval  burrows  until  the  follow- 
ing spring.  A  few  may  leave  the  burrows  in  the  fall  and  con- 
struct others  in  the  twigs  of  apple  or  other  plants  in  which  to 
hibernate.  In  the  spring,  however,  they  begin  their  destructive 
work  early,  burrowing  into  the  axils  of  the  grape  and  occasionally 
also  into  other  plants.  This  is  undoubted^  partly  for  food,  but 
seems  largely  mahcious,  for  it  certainlj^  has  nothing  to  do  with 
egg-laying.  .  .  .  The  eggs  are  laid  chiefly  in  May  or  April  in 
its  southern  range,  and  the  larvae  develop  during  summer,  trans- 
forming to  beetles  and  pupae  in  the  fall.  On  the  Pacific  coast 
a  closely  allied,  but  somewhat  larger  species  (Amphicerus  puncti- 
pennis  Lee.)  .  .  .  probably  has  similar  .  .  .  habits  .  .  ." 

Control. — All  diseased  wood  and  prunings  should  be  removed 
in  late  spring,  thus  destroying  the  material  in  which  the  larvae 
develop.  If  this  is  neglected  and  the  beetles  appear  in  the  vine- 
yard, the  only  means  of  stopping  their  depredations  is  to  cut 
out  by  hand  the  affected  parts  and  destroy  the  beetles.  On 
warm  days  the  beetles  may  sometimes  be  collected  while  running 
over  the  vines. 

The  Grapevine  Flea-beetle  * 

When  the  grape  buds  are  swollen  in  the  spring  they  are  often 
attacked  by  numbers  of  little  blue  or  greenish  beetles  which  eat 
out  or  entirelj^  consume  them.  When  abundant  these  little 
beetles  may  destroy  all  the  buds  on  a  vine,  thus  greatly  retarding 
the  leafing  out  or  even  occasionally  killing  the  plant.  The  beetle 
is  about  one-fifth  inch  long,  of  robust  shape,  and  possesses  the 
thick  thighs  characteristic  of  flea-beetles,  which  enable  it  to  jump 
a  considerable  distance  when  disturbed.  It  is  common  through- 
out the  States  east  of  the  100th  meridian  and  nearly  related 
species  do  similar  damage  on  the  Pacific  Coast.  (See  Quayle, 
I.e.)     The  wild  grape  is  undoubtedly  the  natural  food-plant  of 

*  Haltica  chalybea  HI.  Family  Chrysomelidce.  See  Quaintance,  I.e.; 
Hartzell,  I.e.;  and  M.  V.  Slingerland,  Bulletin  157,  Cornell  Univ.  Agr.  Exp. 
Sta. 


452      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

the  species,  though  it  is  occasionally  found  on  plum,  apple,  pear, 
quince,  blue  beech  and  elm. 

Life  History. — After  feeding  a  few  days  the  female  beetles 
commence  to  lay  their  eggs  in  cracks  of  the  bark  at  the  base  of 
the  buds,  or  in  any  crevice  or  in  the  cavity  eaten  out  of  the  bud 
by  the  beetle,  or  sometimes  on  the  foliage.  The  eggs  are  a  long 
oval  shape,  one-fortieth  inch  long,  and  of  a  dark  straw-yellow 
color.     The  eggs  hatch  just  as  the  young  leaves  are  expanding. 


Fig.  379. — The  grapevine  flea-beetle  {Haltica  chalyhea  III.):  a,  adult  with 
hind  leg  at  right  further  enlarged;  h,  larva,  much  enlarged;  c,  beetles 
and  larvae  on  foliage — natural  size;  d,  beetle  feeding  on  bud;  e,  diseased 
beetles.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

and  upon  them  the  young  larvae  feed  greedily.  The  larvse  feed 
on  the  upper  surface  of  the  leaf,  eating  out  irregular  holes  through 
the  skin  and  into  the  soft  tissue,  and  become  full  grown  in  three 
or  four  weeks.  The  young  larvse  are  a  very  dark  brown,  but 
when  grown  they  are  one-third  inch  long  and  a  dark  yellowish- 
brown,  marked  by  regular  rows  of  blackish  tubercles  each  of 
which  bears  a  small  hair.  The  head,  anal  and  prothoracic  plates 
and  legs  are  black.  The  full-grown  larva  drops  to  the  ground 
and  an  inch  or  two  beneath  the  surface  makes  a  small  cell  in  which 


INSECTS  INJURIOUS  TO  THE  GRAPE 


453 


it  transforms  to  a  white  pupa,  from  which  the  adult  beetle 
emerges  in  one  or  two  weeks.  In  New  York  there  is  but  a  single 
generation,  but  more  than  one  generation  may  occur  in  the 
South.  Upon  emerging  the  beetles  feed  on  the  grape  and  other 
plants,  doing  no  particular  damage,  and  enter  hibernation  in 
the  fall. 

Control.— Where  vineyards  are  regularly  sprayed  with  arsen- 
icals  there  will  be  but  little  trouble  with  the  flea-beetles,  as  the 
grubs  are  very  easily  destroyed  on  the  foliage.  In  neglected 
vineyards  the  beetles  often  become  very  abundant  and  may  be 


Fig.  380. — Eggs  of  the  grapevine  flea-beetle,  natural  size  at  a,  and  enlarged 
at  6.     (After  SHngerland.) 

quite  destructive  in  such  localities.  Where  it  is  necessary  to 
combat  the  beetles  to  prevent  injury  to  the  buds,  close  watch 
should  be  kept  for  them  and  the  buds  should  be  thoroughly 
sprayed  at  once,  using  4  pounds  of  arsenate  of  lead  per  barrel. 
Usually  this  wiU  need  to  be  appKed  just  as  the  buds  are  becoming 
well  swollen,  and  must  be  applied  promptly  and  thoroughly, 
as  the  beetles  work  quickly  and  a  day's  delay  may  mean  the 
destruction  of  the  buds.  In  a  small  vineyard  or  on  a  few  vines 
the  beetles  may  be  collected  by  hand  in  the  early  morning  when 
they  are  sluggish,  or  may  be  jarred  to  canvas-covered  frames 
kept  saturated  with  kerosene  placed  beneath  the  vines. 


454     INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Rose-chafer  * 

About  the  time  the  grape  is  in  bloom,  immense  swarms  of 
the  common  Rose-chafers  or  Rose-bugs  often  appear,  covering 
the  plants,  feeding  on  the  blossoms,  later  attacking  the  young 
fruit  and  foliage,  and  sometimes  eating  the  leaves  quite  bare  except 
the  larger  veins.  The  chief  damage,  however,  is  done  by  destroy- 
ing the  blossoms  or  newly  set  fruit,  or  by  so  injuring  the  young 
berries  that  they  are  misshapen  and  worthless     The  beetle  is 


Fia.  381. — The  rose  chafer  (Macrodactylus  subspinosus  Fab.):  a,  beetle; 
b,  larva;  c,  d,  mouth-parts  of  same;  e,  pupa — -all  much  enlarged;  /, 
beetles  at  work  on  foliage — natural  size.  (After  Marlatt,  U.  S.  Dept. 
Agr.) 

about  one-third  inch  long,   of  a  Ught-brownish  color,   covered 

with  numerous  lighter  hairs,  and  has  very  long  spiny  legs,  which 

always  seem  to  be  in  its  way  and  make  it  most  awkward  and 

clumsy.     It  IS  a  very  general  feeder,  being  common  on  roses, 

from  which  the  common  name  is  received,  and  also  on  such  orna- 

*  Macrodactylus  subspmosus  Fab.  Family  Scarabcridoe.  See  Quaintance, 
I.e.;  Hartzell,  I.e.;  J.  B.  Smith,  Bulletin  82,  N.  J.  Agr.  Exp.  Sta.;  Fred  John- 
son, Bulletin  97,  Part  III,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  and 
F.  H  Chittenden,  Farmers'  Bulletin  721,  U  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  THE  GRAPE  455 

mentals  as  Spiraea  and  Deutzia,  while  it  frequently  injures  the 
blossoms  of  apple,  plums,  cherries  and  peaches,  and  when  very 
abundant  will  attack  various  vegetables,  grasses,  and  grains. 
The  species  occurs  commonly  from  Canada  to  Virginia  and  Tennes- 
see and  westward  to  Colorado,  and  in  Texas  and  Oklahoma,  but 
seems  to  do  but  Kttle  damage  west  of  the  Mississippi,  being  most 
injurious  in  the  Middle  States.  It  is  particularly  destructive 
where  there  are  areas  of  light  sandy  soil  grown  up  in  grasses  and 
weeds,  upon  the  roots  of  which  the  larvae  feed. 

Life  History. — After  feeding  three  or  four  weeks  the  beetles 
suddenly  disappear.  During  the  middle  of  June,  in  New  Jersey, 
the  females  lay  from  12  to  20  eggs,  depositing  them  in  the  soil 
singly.  These  hatch  in  two  to  three  weeks  and  the  larvsB  feed 
on  the  roots  of  various  grasses  and  possibly  weeds  and  other 
vegetation.  They  become  nearly  full  grown  by  fall,  when  they 
go  below  the  frost  line  and  hibernate  over  winter.  The  larva 
looks  very  much  Hke  a  small  white  grub,  which  it  closely  resembles 
in  every  way,  and  is  about  three-quarters  inch  long  when  full 
grown  (Fig.  381,  6).  In  the  spring  the  grubs  come  near  the 
surface  of  the  soil  and  enter  the  pupa  stage,  which  lasts  from  ten 
to  thirty  days  according  to  the  temperature.  There  is  but  one 
generation  a  year,  and  the  injury  is  done  by  the  beetles  during  the 
three  or  four  weeks  they  are  abroad. 

Control. — When  the  beetles  are  very  abundant  the  only  satis- 
factory method  of  control  is  to  pick  them  by  hand  or  jar  them 
from  the  vines  onto  frames  from  which  they  may  be  collected. 
In  jarring,  an  umbrella-shaped  frame  covered  with  canvas  or, 
preferably,  oilcloth,  which  slopes  to  a  can  of  kerosene  at  the 
bottom,  is  often  used,  being  somewhat  similar  to  that  used  for 
the  plum  curculio.  This  is  held  under  the  vines  and  they  are 
sharply  jarred  or  shaken,  when  the  beetles  will  drop  to  the 
frame  particularly  in  early  morning.  Handpicking  into  a  can  of 
kerosene  and  water  is  probably  the  most  common  method,  how- 
ever. Where  the  beetles  are  not  excessively  abundant  they  have 
been  controlled  in  some  cases  by  thorough  spraying  with  arsenate 
of  lead,  5  to  10  pounds  per  barrel,  preferably  applied  with  Bor- 
deaux mixture,  and  recent  experiments  of  the  N.  Y.  Agricultural 
Experiment  Station  with  5  pounds  of  arsenate  of  lead  and  12 
pounds  of  glucose  per  barrel  gave  excellent  results.     The  num- 


456      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

bers  of  the  pest  may  also  be  much  reduced  by  keeping  down  the 
grass  and  weeds  in  the  vineyard,  and  particularly  on  light  sandy 
soils  adjoining  lands  should  be  broken  up  and  cultivated  in  annual 
crops  as  far  as  possible,  thus  reducing  the  breeding  grounds  of  the 
pest.  By  bagging  the  grapes  as  soon  as  the  fruit  is  set  the  clusters 
may  be  protected  from  this  as  well  as  other  pests  and  diseases 
wherever  such  treatment  is  practicable. 

All  recent  work  seems  to  indicate  that  the  treatment  with 
arsenate  of  lead  and  molasses  is  the  best  means  of  control.  The 
spray  should  be  applied  before  the  beetles  appear  in  large  num- 
bers and  it  may  be  necessary  to  repeat  it  once  or  twice. 

Self-boiled  Hme-sulphur  has  been  said  (Headlee)  to  act  as  a 
repellant,  but  there  is  need  for  more  experimental  work  before 
this  can  be  generally  established. 

The  Grape  Leaf-hopper  * 

Wherever  the  grape  is  grown  in  the  United  States  and  Canada, 
the  fohage  will  be  found  more  or  less  infested  with  the  small 
Leaf -hoppers,  often  locally  called  "  thrips,"  which  feed  and  breed 
on  the  under  surface  of  the  leaves  during  the  season.  By  late 
summer  the  vines  may  be  covered  with  the  hoppers,  which  will 
fly  off  in  clouds  when  disturbed,  and  every  year  there  is  serious 
injury  in  various  localities.  The  injury  is  done  by  the  httle 
hoppers  sucking  out  the  juices  of  the  leaves  through  their  tube- 
hke  mouth-parts.  A  small  white  spot  first  appears  around  the 
feeding  puncture,  due  to  the  l(5ss  of  chlorophyll  in  the  leaf,  and 
when  the  punctures  have  become  numerous  the  leaf  has  a  varie- 
gated appearance.  As  the  injury  increases  the  leaf  yellows  and 
finally  dries  up  and  falls  to  the  ground.  Where  it  becomes 
general,  this  injury  reduces  both  the  quantity  and  quality  of  the 
fruit.  The  pest  is  an  insidious  one,  as  it  is  not  usually  noticed 
until  it  becomes  very  abundatit  in  late  summer,  by  which  time 
most  of  the  injury  has  been  done  and  it  is  too  late  to  prevent  it. 
For  this  reason  its  control  has  been  very  generally  neglected  by 
grape  growers  with  a  consequent  loss  the  cause  of  which  is  often 
unsuspected. 

■f^  *  Typhlocyha  comes  Say.  Family  Jassidce.  See  Quaintance,  I.e.;  Hartzell, 
I.e.,  and  Bulletin  359,  N.  Y.  Agr.  Expt.  Sta.;  Quayle,  I.e.;  and  M.  V.  Slinger- 
land,  Bulletin  215,  Cornell  Univ.  Agr.  Exp.  Sta.,  and  Fred  Johnson,  Bulletin 
19,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  THE  GRAPE 


457 


The  adult  hoppers  are  about  one-eighth  inch  long  and  the 
wings  are  prettily  marked  with  yellow  and  red  as  shown  in  Fig. 
382.  "In  summer  the  young  and  adult  insects  are  hght  yellow- 
ish in  color,  but  before  going  into  hibernation,  the  eyes  of  the 
adults  darken  and  the  peculiar  yellow  spots  on  the  wings  change 
to  an  orange  red,  thus  giving  the  hibernating  adults  a  general 
reddish  appearance.  These  darker  markings  on  the  adults  vary 
so  much  that  nine  different  varieties  are  now  recognized,  two  of 
which  are  represented  at  b  and  c,  in  Fig.  382.     Often  several 


(y  Fig.  382. — Grape  leaf-hopper  {Typhlocyha  comes):  a,  adult  female;  h,  adult 
male;  c,  another  form  of  the  species,  showing  variation  in  markings; 
d,  newly-hatched  nymph;  e,  last  stage  nymph;  /,  appearance  of  injured 
leaf;  g,  cast  pupa  skins — a,  e,  much  enlarged;  g,  less  enlarged;/,  reduced. 
(From  Marlatt,  U.  S.  Dept.  Agr.) 

of  the  varieties  may  be  found  together  on  the  same  vines,  but 
usually  one  color  form  largely  predominates."  The  nymphs  are 
a  light  yellowish-green  color  with  lemon-yellow  stripes  on  each 
side  of  the  body.  They  pass  through  five  molts  before  becoming 
adults,  the  wing-pads  gradually  getting  larger  in  the  later  stages. 
No  very  similar  insects  are  common  on  the  grape,  so  that  the 
pest  is  readily  recognized. 

Life  History. — The  adult  hoppers  hibernate  over  winter  under 
leaves,  grass,  or  trash  in  or  near  the  vineyard,  in  neighboring 
woods,  along  ditches  or  fences,  etc.  They  emerge  about  May  1 
in  New  York  and  at  first  feed  on  whatever  succulent  foliage  may 
be  available.    By  the  time  the  grape  foliage  appears  they  have 


458      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

mostly  emerged  and  infest  the  vineyards.  These  hibernating 
hoppers  feed  and  breed  on  the  lower  leaves,  disappearing  about 
the  time  the  first  young  become  adult.  After  a  few  weeks  the 
females  commence  egg-laying,  which  continues  for  about  two 
months.  The  eggs  are  laid  just  beneath  the  surface  of  the  leaf 
in  groups  of  from  six  to  nine,  or  singly,  and  as  they  are  but  one- 
thirty-fifth  inch  long  and  almost  transparent,  they  are  scarcely 
visible  save  for  the  eyes  of  the  embryonic  nymphs.  The  eggs 
hatch  in  nine  to  fourteen  days.  The  young  nymphs  feed  like  the 
adults,  at  first  on  the  lower  leaves,  but  soon  spread  to  all  parts 
of  the  plant.  In  New  York  they  become  grown  in  thirty  to 
thirty-five  days,  and  there  is  but  one  full  generation  a  year, 
with  a  partial  second  generation,  most  of  the  individuals  of 
which  probably  do  not  mature  before  frost.  Feeding  continues 
until  cool  weather,  when  the  adults  enter  hibernation.  In  Col- 
orado, New  Mexico  and  Cahfornia  and  probably  throughout  the 
South,  there  are  two  full  generations  a  year.  In  Cahfornia, 
according  to  Quayle,  the  nymphs  from  eggs  laid  by  the  hibernat- 
ing hoppers  appear  by  the  middle  of  May  and  the  following 
generation  of  nymphs  about  the  middle  of  July. 

Control. — Cleaning  up  all  fallen  leaves  and  trash  in  the  vine- 
yard during  the  winter,  or  plowing  it  under  in  the  early  spring, 
will  reduce  the  number  of  hibernating  hoppers,  and  it  has  been 
observed  that  they  are  much  less  numerous  in  vineyards  where 
clean  culture  is  practiced.  The  burning  over  of  adjacent  mead- 
ows, wood  lots  and  fence  rows  will  also  be  advisable  where 
practicable. 

In  California,  where  the  vines  are  not  trellised,  a  hopper-cage, 
which  has  been  fully  described  by  Quayle,  I.e.,  is  successfully 
used  for  catching  the  hoppers  before  they  commence  to  oviposit 
in  the  spring.  In  the  East  this  could  not  be  used,  but  Professor 
SHngerland  has  shown  that  the  hibernated  hoppers  may  be  caught 
on  sticky  shields  before  they  oviposit. 

However,  it  has  been  found  that  such  methods  of  capturing 
and  destroying  the  adults  are  expensive  and  give  at  best  only 
partial  relief  from  the  trouble.  It  has  been  found  a  much  better 
practice  to  kill  the  nymphs.  This  is  done  very  efficiently  by 
spraying  them  Avith  "  Black-leaf  40 "  at  the  rate  of  1  to  1500, 
applying  the  spray  at  the  time  the  nymphs  are    present  in  the 


INSECTS  INJURIOUS  TO  THE  GRAPE 


459 


greatest  numbers  on  the  under  side  of  the  grape  leaves.  If  this 
is  properly  done,  one  application  will  give  control.  The  time 
for  spraying,  in  the  Northern  States,  will  generally  be  during 
the  latter  half  of  July. 

The  Grape  Leaf-folder  * 

Very  frequently  grape  leaves  are  found  folded  or  rolled 
together,   with   the  interior  surface  more   or   less  skeletonized, 

from  which  a  slender 
larva  will  wriggle  out 
and  fall  or  hang  sus- 
pended on  a  silken 
thread.  The  Grape 
Leaf-folder  occurs 
throughout  the  United 
States,  and  though 
usually  not  injurious, 
sometimes  becomes 
abundant  enough  to 
do  serious  damage. 
The  moth  is  black  with 
white  spots  on  the  wings, 
and  bands  across  the 
abdomen,  as  shown  in 
Fig.  383.  The  larva  is 
about  an  inch  long,  of 
a  greenish-white  color, 
with  head  and  prothoracic  shield  light  brown,  and  with  brown 
spots  on  the  sides  of  the  first  two  thoracic  segments. 

Life  History. — "There  are  two  broods  each  year  in  the  more 
Northern  States  and  three  or  possibly  more  in  the  South.  The 
insect  winters  in  the  pupal  stage  in  the  folded  and  fallen  leaves, 
the  moths  appearing  in  the  spring  shortly  after  the  foliage  puts 
out,  and  the  eggs  are  placed  in  small  patches  here  and  there 
on  the  vine.  Upon  hatching,  the  young  larvae  attack  the  foliage, 
folding  the  leaves  as  stated.  Mr.  Johnson  has  observed  that 
the  larvae  of  the  first  brood  may  attack  bunches  of  grape  blossoms 
and  young  fruit  in  a  way  similar  to  the  grape-berry  moth      In 

*  Desmia  funeralis  Hiibner.  Family  Pyralidm.  See  Quaintance,  and 
Quayle,  1.  c,  also  J.  F.  Strauss,  Bulletin  419,  U.  S.  Dept.  Agr. 


Fig.  383. — ^The  grape  leaf-folder  (Desmia  fun 
er alls  Huhn.):  a,  male  moth  and  enlarged 
antenna  of  same;  b,  female  moth;  c,  larva; 
d,  head  and  thoracic  segments  of  same  en- 
larged; e,  pupa;  /,  tip  of  pupa — enlarged; 
g,  grape  leaf  folded  by  larva.  (After  Mar- 
latt,  U.  S.  Dept  Agr.) 


460 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


three  or  four  weeks  the  larvae  are  full  grown  and  transform  to 
pupae  within  the  folded  leaves,  moths  emerging  eight  or  ten  days 
later.  By  midsummer  and  fall  the  insects  become  quite  abundant, 
and  in  badly  infested  vineyards  the  folded  leaves  are  everywhere 
in  evidence  and  are  quite  conspicuous  from  the  color  of  the  lower 
surface.  In  the  fall  the  larvae  pupate  in  the  folded  leaves  and 
pass  the  winter  in  these  on  the  ground." — Quaintance. 

Control. — Where  but  a  few  larvae  occur  they  may  be  crushed 


Nig  384. — The  white-lined  sphix  Deilephila  Inieata  Fab.) :  a,  moth  b,  pale 
larva;  c,  dark  form  of  larva;  d  pupa — all  natural  size.  (After  Chitten- 
den, U.  S.  Dept.  Agr.) 

by  hand,  and  if  this  is  done  with  the  first  brood  it  will  greatly 
reduce  the  numbers  later  in  the  season.  Vineyards  sprayed 
with  arsenicals  will  be  protected,  as  the  young  larvae  will  be  killed 
before  they  fold  the  leaves.  By  collecting  and  burning  the  fallen 
leaves  or  plowing  them  under  deeply,  many  of  the  hibernating 
pupae  may  be  destroyed. 


INSECTS  INJURIOUS  TO  THE  GRAPE 


461 


Hawk-moth  Larvae  * 

Several  species  of  Hawk-moth  or  Sphinx-moth  larvae  are  com- 
monly found  on  the  vine.  Most  of  them  are  widely  distributed 
throughout  the  country  and  feed  on  wild  grape  and  Virginia 
creeper.     Usually  they  are  not  numerous  enough  to  do  serious 


Fig.  385. — The  achemon  sphinx  (Pholus  achemon  Dru.):  a,  moth;  b,  egg;  c, 
young  larva;  d,  mature  larva;  e,  pupa;  /,  parasitized  larva — all  natural 
size.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

damage,  and  as  they  strip  a  branch  at  a  time,  they  are  readily  seen 

and  may  be  destroyed  before  much  injury  is  done.     Occasionally, 

*  Family  Sphingidoe.     See  O.  Lugger,  4th  Report  State  Ent.  Minn. ;  lad 
M.  Eliot  and  Caroline  M.  Soule,  "Caterpillars  and  their  Moths."  (N.  Y.,  1902). 


462      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

however,  one  or  two  larvae  may  entirely  strip  a  young  vine,  and 
exceptionally  the  larvae  appear  in  considerable  numbers  on  old 
vines,  stripping  them  bare  of  foKage.  They  are  large,  smooth- 
bodied  larvae,  2  to  3  inches  long,  and  may  be  distinguished  from 
those  of  other  famihes  of  moths  by  the  strong  horn  on  the  next 
to  the  last  segment,  which  has  given  them  the  common  name 
of  horn-worms.  In  many  species,  this  horn  is  present  only  in  the 
first  one  or  two  stages  of  the  larva,  disappearing  with  the  next 
molt  and  being  replaced  by  a  bright  eye-spot,  as  shown  in  Fig.  385, 
c,  d.  The  hfe  history  of  the  various  species  is  much  the  same, 
except  that  some  have  only  one,  while  others  have  two  genera- 
tions a  year  in  the  North,  though  most  all  probably  have  two 
generations  in  the  South.  They  hibernate  as  large  dark-brown 
pupae,  3  or  4  inches  below  the  surface  of  the  ground,  and  the 
moths  emerge  in  spring.  The  moths  are  particularly  attracted 
to  petunias,  and  may  often  be  caught  hovering  over  them  at 
night.  The  eggs  are  laid  on  the  foliage,  usually  singly,  and  the 
larvae  hatch  in  a  few  days.  They  eat  ravenously,  and  will  con- 
sume an  enormous  number  of  leaves  within  a  few  days.  Usually 
the  coloration  of  the  larvae  changes  more  or  less  as  they  grow,  so 
that  when  full  grown  they  are  different  from  the  younger  stages. 
When  there  are  two  generations,  the  second  generation  of  larvae 
will  appear  in  late  July,  but  whether  one  or  two  generations  occur, 
the  larvae  maturing  in  late  summer  transform  to  pupae  which 
hibernate. 

Control. — Usually  the  work  of  the  larvae  is  so  conspicuous  and 
they  are  so  easily  found  that  they  may  be  controlled  by  hand- 
picking.  Where  the  vineyards  are  sprayed  regularly  for  other 
pests  there  will  be  but  little  trouble  with  these  larvae,  as  they  will 
be  killed  while  young. 

The  Grape-berry  Moth  * 

The  larvae  of  the  Grape-berry  Moth  are  the  most  common 
cause  of  wormy  grapes.  The  first  generation  of  larvae  web 
together  the  grape  clusters  before  the  blossoms  open  or  soon  after 
the  grapes  are  set,  and  feed  upon  the  clusters.  Later  the  larvae 
bore  into  the  green  and  ripening  fruit,  producing  purplish  spots 

*  Polychrosis  viteana  Clem.  YsuniXy  Tortricidce.  See  Quaintance,  I.e.; 
Hartzell,  I.e.,;  M.  V.  Slingerland,  Bulletin  223,  Cornell  Univ.  Agr.  Exp.  Sta.; 
Gossard  and  Houser,  Circular  63,  Ohio  Agr.  Exp.  Sta.  Dwight  Isely,  Bulletin 
550,  U.  S.  Dept.  Agr.  and  W.  H.  Goodwin,  Bulletin  293,  Ohio  Agr.  Expt.  Sta. 


INSECTS  INJURIOUS  TO  THE  GRAPE 


463 


resembling  the  appearance  of  injury  by  the  black  rot.  The 
berries  decay  from  the  work  of  the  larvae  and  from  the  entrance 
of  fungous  diseases.  The  insect  occurs  throughout  the  United 
States,  but  has  been  particulai'ly  injurious  in  the  Chautauqua, 
N.  Y.,  Erie,  Pa.,  and  Northern  Ohio  grape  belts.  So  far  as  known 
the  grape  is  the  only  food-plant  and  the  species  is  a  native  one, 

though  its  habits  are  very  similar  '  |ik  "^ 

to    a    nearly    related    European 
species. 

The  adult  is  a  little  purplish- 
brown  moth,  with  wings  expand- 
ing not  quite  one-half  inch,  and  


Fig.  386. — The  work  of  the  grape-berry  moth;  infested  cluster  and  single 
berry  opened  to  show  larva  at  work — enlarged.     (After  Slingerland.) 

shaded  with  brownish  markings  as  shown  in  Fig.  387.  The 
ground  color  is  hlaceous  or  leaden-blue  and  the  spots  are  dark 
brown. 

Life  History. — The  moths  appear  in  the  spring  as  the  shoots 
of  the  grape  are  pushing  out,  and  continue  to  emerge  for  some 
weeks.  The  earlier  ones  lay  their  eggs  on  the  blossom  clusters, 
while  the  later  ones  deposit  them  on  the  young  grapes.  The 
minute  flat,  scale-like  eggs  are  stuck  to  the  surface  of  the  stems 
or  berries,  and  look  hke  small  gUstening,  whitish  spots.  The 
little  larvsB  hatching  from  them  feed  on  the  blossoms  and  small 
berries,  webbing  the  clusters  together,  and  might  do  much  more 
damage  than  the  later  generations  were  it  not  that  they  are  much 
fewer  in  number,  there  being  a  great  mortality  of  the  insects  over 
winter.  The  larvse  become  full  grown  in  about  three  weeks. 
The  mature  larva  is  about  three-eighths  inch  long,  varying  in 
color  from  dark  greenish  to  dark  purplish,  with  a  light-brown 


Fig.  387. — Grape-Berry  Moth:  1,  Larva;  2,  Pupa  (ventral  aspect)  in  cocoon; 
3,  Pupa  (dorsal  aspect.);  4,  5,  Adult.  All  greatly  enlarged.  (After 
Isely,  I.e.) 

464 


INSECTS  INJURIOUS  TO  THE  GRAPE  465 

head  and  black  thoracic  shield.  The  body  is  covered  with 
numerous  faintly  outlined  darker  spots,  from  which  arise  whitish 
hairs.  The  larva  cuts  out  a  piece  of  a  leaf  on  three  sides,  folds  it 
over  and  fastens  the  free  edge  to  the  leaf  with  silk.  The  fold  is 
then  lined  with  a  thin  layer  of  silk,  making  a  thin  cocoon  in  which 
it  transforms  to  a  light  greenish-brown  pupa,  from  which  the 
moth  emerges  twelve  to  fourteen  days  later.  The  moths  of  the 
second  and  later  generations  place  their  eggs  on  the  berries  and 
the  larva?  bore  into  them  and  feed  on  the  pulp  and  seeds.  In 
New  York  the  moths  of  the  second  generation  appear  in  early 


J 


yi 


Fig.  388. — Grape  leaf  sho'n'ing  cocoons  in  the  making  and  finished  by  grape- 
berry  moth  caterpillars — natural  size.     (After  Slingerland.) 

July  and  the  second  generation  of  larvse  occurs  during  July  and 
August.  In  New  York  those  larvse  of  the  second  generation 
which  mature  before  mid-August  pupate  and  give  rise  to  a  third 
generation,  while  those  maturing  later  transform  to  pupse,  but 
hibernate.  Often  there  is  nearly  a  complete  third  brood  in  that 
latitude,  and  farther  south  there  are  undoubtedly  at  least  three 
generations.  The  winter  is  passed  in  the  pupal  stage  in  the 
cocoons,  which  break  off  from  the  fallen  leaves. 

Control. — Infested  berries  should  be  picked  off  both  to  destroy 
the  larvse  and  to   prevent  the  spreading  of  fungous  diseases. 


466      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Plowing  under  the  fallen  leaves  either  in  fall  or  early  spring 
should  result  in  burying  many  of  the  pupae  so  as  to  prevent  the 
escape  of  the  moths,  and  is  good  practice  for  other  grape  pests. 
The  principal  reliance  should  be  placed  upon  spraying  with  arse- 
nate of  lead,  3  pounds  per  barrel,  applied  with  Bordeaux  mixture, 
to  which  a  soap  "sticker"  should  be  added  to  make  the  mixture 
more  adhesive  to  the  berries.  The  first  spraying  should  be  made 
before  the  blossoms  open,  to  catch  the  early  larvae;  the  second 
should  be  made  as  the  grapes  finish  blooming;  and  the  third, 
early  in  July.  The  addition  of  the  "sticker"  is  most  important 
in  the  last  spraying,  when  the  berries  are  partly  grown.  The 
spray  must  be  applied  with  sufficient  number  of  nozzles  and 
pressure  to  penetrate  the  foliage  and  cover  the  clusters  thoroughly. 
'  Isely  (I.e.)  shows  conclusively  that  it  is  much  more  satis- 
factory to  apply  the  spray  by  hand  with  short  leads  of  hose 
and  short  spray  rods,  called  trailers,  than  it  is  to  depend  upon 
any  fixed  arrangement  of  the  nozzles  which  does  away  with  the 
hand  work.  Difference  in  efficiency  between  the  two  methods 
favored  the  trailers  by  from  15  to  20  per  cent  and  more  than! 
repaid  the  extra  cost. 

To  preserve  some  clusters  in  extra  fine  condition  or  to  pro- 
tect grapes  on  a  small  number  of  vines,  paper  bags  are  some- 
times tied  over  the  clusters  as  soon  as  the  berries  have  set. 

The  Grape  Curculio  * 

The  larvae  of  the  Grape  Curculio  feed  on  the  pulp  and  seeds 
of  the  berries,  causing  wormy  grapes,  much  as  do  those  of  the 
berry-moth.  The  larvae  may  be  readily  distinguished,  for  those 
of  the  curculio  are  white,  footless  grubs,  while  those  of  the  berry- 
moth  are  greenish,  with  well-developed  legs,  and  are  quite  agile, 
wriggling  away  quickly  when  disturbed.  The  adult  curculio  is 
a  small,  brown,  robust,  snout-beetle  about  one-tenth  inch  long, 
and  nearly  as  broad.  It  is  very  difficult  to  see,  looking  Uke  a  bit 
of  dirt  or  the  excreta  of  some  of  the  larger  caterpillars  common 
on  the  vine.  It  is  common  from  Arkansas  to  Minnesota  east- 
ward to  New  York  and  North  Carofina.  It  has  been  particularly 
injurious  in  West  Virginia,  and  seems  to  be  most  harmful  in 
that  latitude. 

*  Cra'ponius  incequalis  Say.  Family  Curculionidce.  See  Quaintance, 
I.e.,  and  Fred  E.  Brooks,  Bulletin  100,  W.  Va.  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  THE  GRAPE 


467 


Life  History. — The  beetles  hibernate  over  winter  in  or  near 
the  vineyards,  especially  along  the  edge  of  woodlands.  They 
appear  in  the  spring  about  the  time  the  grapes  blossom  and  feed 
upon  the  foliage  for  three  or  four  weeks  until  the  berries  are 


Fig.  389. — The  grape  curculio  {Craponius  inaqualis  Say):  a,  beetle;  6,  head 
of  same  from  side;  d,  larva  from  above;  e,  same  from  below;  /.  pupa — 
all  much  enlarged.     (After  Quaintance,  U.  S.  Dept.  Agr.) 

about  one-fourth  grown.  The  beetles  cut  small  characteristic 
holes  in  the  leaves,  and  this  habit  of  feeding  on  the  foliage  so 
long  makes  it  possible  to  kill  them  with 
arsenicals  before  oviposition  is  commenced. 
In  West  Virginia  the  females  begin  egg- 
laying  late  in  June,  most  of  the  eggs  being 
laid  in  early  July,  but  egg-laying  may 
continue  for  eighty-one  days,  during  which 
time  a  female  will  lay  an  average  of  257 
eggs.  The  female  excavates  a  small  cavity 
in  the  berry  in  which  the  egg  is  placed  and 
hatches  in  four  to  six  days.  Infested  berries 
often  show  a  purphsh  spot  around  the  egg- 
puncture.  The  larva  bores  in  the  pulp  and 
in  three  or  four  days  reaches  the  seed, 
which  is  then  devoured.  The  larva  becomes  full  grown  in  twelve 
to  fifteen  days,  when  it  eats  its  way  out  of  the  berry  and  drops 
to  the.ground  in  search  of  a  suitable  place  to  pupate.  The  mature 
larva  is  white,  about  one-third  inch  long,  tapering  from  the  middle 
of  the  body  toward  either  end,  without  legs,  and  clothed  with  fine 
short  hairs.     The  larvae  make  small  earthen  cells  under  stones, 


Fig.  300. — The  prape  cur- 
culio in  act  of  egg-lay 
ing — natural  size;  e, 
showing  position  of  egg 
in  grape — enlarged. 
(After  Brooks.) 


468      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


lumps  of  earth  or  just  below  the  surface  of  the  soil,  and  in  them 
transform  to  pupae,  from  which  the  beetles  emerge  in  eighteen 

to  nineteen  days.  Thus  the  com- 
plete life  cycle  from  egg  to  adult 
requires  thirty-five  days.  The 
hibernating  beetles  are  still  abroad 
when  the  new  beetles  appear,  and 
Brooks  states  that  the  average 
life  of  a  beetle  is  one  year  and 
nineteen  days.  Although  the 
beetles  of  the  new  brood  lay 
some  eggs,  but  few  of  them 
develop,  and  in  West  Virginia 
there  is  practically  but  one 
generation,  although  farther 
south  a  second  generation  may 
occur.  The  beetles  feed  until  fall,  when  they  enter  hibernation. 
Control. — As  the  beetles  feed  so  long  on  the  foliage  in  early 


Fig.    391. — Grape  curculio  larvae — 
natural  size.      (After  Brooks.) 


Fig.  392. — Grapes  showing  egg-punctiires  of  grape  curculios.     (After  Brooks.; 

summer  they  may  be  readily  killed  by  spraying  with  arsenicals 
as    advised    for    the    berry-moth    and    grape-root-worm    beetle. 


Fig.  393. — Showing  the  resemblance  of  the  grape  curculios  at  2  to  excrement 
of  sphinx  caterpillars  at  1,  and  mummied  grapes  at  3.     (.\fter  Brooks.) 


INSECTS  INJURIOUS  TO  THE  GRAPE  469 

Thorough  cultivation  in  niidsuninier  would  doubtless  destroy- 
some  of  the  pupae  in  the  same  manner  as  in  the  case  of  the  root- 
worm.  Infested  fruit  may  be  collected  and  destroyed  as  for 
the  berry-moth  with  equally  good  results.  Where  spraying  is 
regularly  practiced  there  probably  will  be  little  need  of  resort 
to  other  methods. 


CHAPTER  XXIV 

SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS* 

The  San  Jose  Scale  f 

Probably  the  most  serious  of  all  the  insect  pests  of  the  orchard 
is  the  San  Jose  Scale,  for  it  will  kill  young  trees  in  two  or  three 
years,  and  old  trees  must  be  sprayed  annually  to  keep  it  under 
control.  So  insidious  is  the  attack  of  the  pest  to  those  unfamiliar 
with  it  that  it  has  killed  many  thousands  of  trees  before  the 
owners  suspected  its  presence.  It  may  be  most  readily  detected 
on  the  fruit,  which  becomes  spotted  with  small  red  circles  which 
form  around  the  scales,  but  usually  the  fruit  is  not  attacked 
until  the  tree  is  badly  infested.  On  the  young  twigs  and  along 
the  veins  of  the  leaves  a  similar  reddish  discoloration  appears 
around  the  scales.  The  trunk  and  branches  covered  with  scales 
have  a  rough  grayish  appearance,  as  if  they  had  been  coated 
with  dark  ashes.  By  scraping  the  surface  the  soft,  juicy,  yel- 
lowish insects  will  be  revealed  beneath  the  covering  scales.  If 
a  single  female  insect  be  examined  it  will  be  found  that  it  is 
covered  by  a  small,  circular  scale,  varying  from  grajdsh  to  blackish 
in  color,  formed  of  concentric  circles,  the  centre  of  which  is  quite 
convex  and  forms  a  "nipple,"  which  is  yellowish  and  shining 
when  the  surface  is  rubbed  off.  If  this  scale  be  raised  with  a 
pin,  beneath  it  may  be  seen  a  small,  soft,  oval,  orange-colored 
object,  which  is  the  true  female  insect.  She  is  an  almost  shape- 
less mass  of  protoplasm,  lacking  head,  legs  and  eyes,  only  the 
thread-like  mouth  parts  and  anal  plate  being  distinct.  The  scale 
itself  is  merely  a  waxy  covering  secreted  by  the  insect  beneath. 
The  scale  of  the  male  is  smaller  and  somewhat  elongated,  the 
nipple  being  at  the  larger  end. 

*  See  Quaintance  and  Seigler,  Farmers'  Bulletin  908,  U.  S.  Dept.  Agr. 

^Aspidiotus  perniciosus  Comstock.  Family  Coccidce.  See  C.  L.  Mar- 
latt,  Bulletin  62,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  and  the  numer- 
ous publications  of  many  of  the  experiment  stations,  listed  in  his  bibliography. 

470 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS  471 

Injury  by  this  species  was  first  noticed  near  San  Jose,  Cal., 
about  1880  where  the  scale  was  most  destructive  and  was  inves- 
tigated by  Professor  J.  H.  Conistock,  who  first  described  it. 
About  1887  it  was  brought  east  on  Japanese  plum  trees  secured 
by  Eastern  nurseries  and  was  distributed  by  them  on  young 


Fig.  394. — Peach  twigs  infested  with  the  San  Jose  scale.  On  the  twig  at 
the  right  a  scale  has  been  turned  back  showing  the  female  insect — 
enlarged.     (After  W.  E.  Britton.) 

trees,  so  that  in  1893  it  was  discovered  in  orchards  in  Maryland 
and  Virginia.  Since  then  it  has  been  spread  on  nursery  trees  to 
practically  every  State.  Investigations  made  by  C.  L.  Marlatt 
in  1901  showed  that  the  insect  is  undoubtedly  a  native  of  east- 


472     INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


central  China,  and  was  probably  brought  to  this  country  on 
flowering-peach  or  some  ornamental  plant. 

Life  History. — The  winter  is  passed  by  partly  grown  insects 
under  the  scales,  which  begin  to  feed  with  the  bursting  of  the 
buds  in  spring.  In  the  latter  part  of  April  the  insects  have  become 
full  grown  in  the  District  of  Columbia,  and  the  males  emerge 
and  fertilize  the  females.  The  male  is  a  small,  yellowish,  two- 
winged  fly.  The  males  emerge  at  night  and  are  so  small  they  are 
seldom  seen  unless  reared.  About  a  month  later  the  females  com- 
mence to  give  birth  to  live  young  and  continue  to  do  so  for  some 
six  weeks.      This  species  differs  from  most  scales  in  having  no  egg 

stage,  the  eggs  hatching  in  the  body  of 
the  female.  The  young  insects  are  very 
small,  yellowish  in  color,  and  resemble 
small  mites.  They  have  six  legs,  a  pair 
of  antennae,  and  a  long  thread-like  beak 
through  which  the  food  is  sucked,  as 
shown  in  Fig.  398.  The  young  insect 
moves  about  freely  for  from  twelve  to 
thirty-six  hours,  then  thrusts  its  beak 
into  the  bark  or  fruit,  and  if  a  female  does 
not  move  again.  White,  waxy  filaments 
soon  exude  from  over  the  body,  and 
in  a  couple  of  days  the  insect  is  entirely 

T.     „^.  ^  -  --^'-  covered  by  them,  and  as  they  mat  down 

Fig.  395.— Pear  injured  by  the  ,    .    /  -,     i  •  •,  ^    ■.      m^  ■ 

San  Jose  scale  showing  the  a  scale  is  formed  which  conceals  it.    i  his 

discolored  spots.  young  scale  is  whitish  with  a  prominent 

nipple  in  the  center.  After  the  first  molt,  the  females  lose  eyes, 
legs,  and  antennae,  for  which  they  have  no  further  use.  Nour- 
ished by  the  sap  of  the  plant  the  insect  develops  rapidly  and 
is  full  grown  in  about  a  month.  In  the  District  of  Columbia 
there  are  four  or  five  generations  a  year,  in  the  South  there  are 
probably  more  generations,  while  at  the  northern  hmit  of  the 
species  there  are  two  or  possibly  three  generations,  as  breeding 
continues  until  after  killing  frost.  As  with  other  small  insects,  it 
is  the  remarkable  power  of  reproduction  to  which  the  destructive- 
ness  of  the  pest  is  due.  Thus  it  has  been  estimated  that  at  Wash- 
ington, D.  C,  the  progeny  of  a  single  female  would  number 
3,216,080,400  by  fall,  if  all  were  to  survive.    It  is  not  surprising, 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 


473 


tnerefore,  that  a  tree  with  but  a  few  scales  on  it  in  spring  will 
be  covered  by  them  and  the  fruit  unfit  for  market  in  the  fall, 


P^G.  396. — Peach  leaf  bearing  San  Jos6  scales  along  veins. 

and  that  with  these  millions  of  Uttle  beaks  pumping  out  the  sap 

and  poisoning  the  tissues  a  tree  soon  succumbs. 

The  pest  has  been  spread  mostly  by  being  transported  on 

nursery  trees.    Trees  infested  from  the  nursery  will  usually  have 

more  scales  on  the  lower  trunk, 
from  which  they  will  spread 
to  the  limbs,  while  those  infested 
from  neighboring  trees  will  have 
more  scales  on  the  young  wood. 
Where  the  pest  is  abundant 
the  young  insects  are  undoubt- 
edly blown  from  tree  to  tree  by 
the  wind,  or  they  may  be  carried 
on  the  feet  of  birds  or  insects, 
or  brushed  off  and  carried  by 
persons  or  teams  working  in  the 
orchard.  The  insect  has  been 
found  on  a  long  list  of  plants, 
but   on   many  of    them   it   is 


Fig.  397.— Adult  female  San  Jos6 
scale,  with  scale  removed  to  ex- 
pose the  insect.      (After  Alwood.) 


largely  accidental.  Injury  is  practically  confined  to  plants  of  the 
Rosace  ce,  which  family  includes  all  our  common  deciduous  fruits. 
Of  the  orchard  trees  peach,  pear,  Japanese  plum,  apple  and 
quince  are  most  injured  in  the  order  named,  while  cherry  and 
European  plum  are  less  injured. 

Control. — As  yet  no  spray  has  been  found  for  use  in  summer 
which  will  more  than  check  the  increase  of  the  pest  without 
injury  to  the  tree,  and  summer  spraying  is  resorted  to  only  when 


474     INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

winter  treatment  has  been  neglected  or  has  proven  inefficient. 
10  or  15  per  cent  kerosene  emulsion,  dilute  miscible  oils,  dilute 
lime-sulfur  mixture,  or  whale-oil  soap,  1  pound  to  4  or  5  gallons, 
may  be  used  for  summer  spraying. 

On  the  Pacific  Coast  trees  are  very  generally  fumigated  with 
hydrocyanic  acid  gas  *  for  this  and  other  scale  insects,  but  the 


Fig.  398. — Young  larva  and  developing  San  Jos6  scale  (Aspidiotus  perniciosus 
Comst ) :  a,  ventral  view  of  larva,  showing  sucking  beak  and  setse  sepa- 
rated, with  enlarged  tarsal  claw  at  right;  b,  dorsal  view  of  same,  still 
more  contracted  and  with  the  first  waxy  filaments  appearing;  c,  dorsal 
and  lateral  views  of  same,  somewhat  contracted,  illustrating  further 
development  of  wax  secretion ;  d,  later  stage  of  the  same  dorsal  and  lateral 
views,  showing  matting  of  wax  secretions  and  first  form  of  young  scale- — 
all  greatly  enlarged.     (After  Howard  and  Marlatt,  U.  S.  Dept.  Agr.) 

treatment  has  never  come  into  favor  in  the  East,  principally, 
perhaps,  because  of  the  larger  trees  ^nd  the  more  scattered  nature 
of  the  fruit  industry. 

Practically  the  only  methods  now  used  in  the  East  consist  in 
spraying  the  dormant  trees  with  washes  which  penetrate  the 
scales  and  destroy  the  insects.     This  may  be  done  more  effec- 

*See  C.  W.  Woodworth,  Bulletins  122  and  152,  Cal.  Agr.  Exp.  Sta.; 
R.  S.  Woglum,  Bulletins  79  and  90,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS  475 

tively  if  the  trees  are  pruned  and  headed  in  so  as  to  reduce  the 
wood  to  be  covered.  Rough  bark  should  be  scraped  off  so  that 
the  scales  beneath  may  be  reached.  Badly  infested  trees  should 
be  sprayed  in  the  early  winter  as  soon  as  they  have  hardened 
up  and  again  in  the  spring  just  as  the  buds  commence  to  swell.  The 
spring  spraying  will  suffice  for  trees  slightly  infested.  Every  bit  of 
bark  on  the  tree  must  be  thoroughly  wet,  so  none  will  escape. 
Lime-sulfur  mixture  seems  to  be  the  favorite  wash  for  winter 
spraying  at  present,  as  it  not  only  kills  the  scale,  but  aids  in  the 
control  of  many  fungous  diseases.  Miscible  oils  are  also  exten- 
sively used  and  have  a  certain  advantage  on  hairy  apple  shoots 
and  on  badly  infested  trees,  as  they  are  more  penetrating  and 
spread  better.  Kerosene  or  crude  oil  emulsion  containing  20 
to  25  per  cent  of  oil  was  the  first  remedy  to  be  used  and  is  still 
extensively  employed.  Whale-oil  soap,  at  the  rate  of  2  pounds 
to  the  gallon,  applied  hot,  is  effective,  but  is  too  expensive  for 
large  users. 

The  Fruit-tree  Bark-beetle  * 

If  the  outer  bark  is  punctured  by  numerous  small  ''worm- 
holes"  so  that  it  looks  as  if  it  had  been  struck  with  a  charge 
of  bird-shot,  it  indicates  the  presence  of  the  fruit-tree  bark-beetle 
or  some  nearly  related  species  (see  p.  477).  Usually  more  or 
less  gum  exudes  from  the  holes,  particularly  on  stone  fruits. 
Diseased  or  weak-growing  trees  are  most  subject  to  attack,  but 
occasionally  serious  damage  is  done  to  perfectly  healthy  trees, 
especially  when  young.  Injury  is  largely  due  to  allowing  dead 
and  dying  trees  to  stand  in  the  orchard,  thus  encouraging  the 
breeding  of  the  pest  in  them  and  its  spread  to  healthy  trees. 
"Another  form  of  injury  is  the  destruction  at  the  beginning  of 
spring  of  small  twigs,  together  with  the  leaves  which  they  bear. 
The  beetles  are  also  reported  to  destroy  leaves  by  boring  into  the 
base  of  the  buds  at  their  axils."  The  holes  in  the  bark  are  caused 
by  the  exit  of  the  small  parent  beetles  and  by  their  subsequent 
entrance  to  deposit  eggs.  The  adult  beetle  is  about  one-tenth 
inch  long,  by  a  third  as  wide,  and  of  a  uniform  black  color,  except 
the  tips  of  the  wing-covers  and  parts  of  the  legs,  which  are  red. 

*  Ecoptogaster  rugulosus  Ratz.  Family  Scolytidoe.  See  F.  H.  Chittenden 
Circular  29,  Division  of  Entomology,  U.  S.  Dept.  Agr.,  and  F.  E.  Brooks, 
Farmers'  Bulletin  763,  ibid.,  H.  A.  Gossard,  Bulletin  264,  Ohio  Agr.  Exp. 
Station. 


476      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Life  History. — The  beetles  emerge  from  the  trees  in  April  and 
May  in  the  Middle  States.  The  female  burrows  through  the 
bark,  and  partly  in  it  and  partly  in  the  sap-wood  she  eats  out  a 
vertical  gallery  or  brood  chamber,  along  the  sides  of  which  at 
short  intervals  she  gnaws  out  little  pockets  in  which  she  places 
her  eggs.  The  larvae  hatching  from  these  eggs  excavate  little 
side  galleries,  which  branch  out  and  widen  as  the  larvae  increase 


Fig.  399. — One  of  the  most  imijoitiuit  iiali\c  cncmios  of  the  San  Jose  scale, 
a  little  black  ladybird-beetle  [Microivtisea  7nisella):  a,  beetle;  b,  larva; 
c,  pupa;  d,  beetles,  larvae,  and  pupae,  among  scales — all  greatly  enlarged. 
(After  Marlatt,  U.  S.  Dept.  Agr.) 

in  size  (Fig.  401).  The  larvae  become  mature  in  about  three 
weeks,  when  they  foi'm  cells  at  the  ends  of  their  burrows  and 
transform  to  pupae,  from  which  the  adult  beetles  emerge  about  a 
week  later.  There  are  probably  three  generations  a  year  in  the 
Middle  States  according  to  Dr.  Chittenden. 

Were  it  not  for  the  effective  work  of  parasitic  and  predaceous 
insects  which  prey  upon  it,  this  insect  would  be  a  most  serious 
pest.  One  of  the  most  valuable  of  these  is  a  little  chalcis-fly  * 
of  which  Dr.  Chittenden  bred  92  specimens  from  72  of  the  develop- 

*  Chiropachis  colon  Linn. 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 


477 


ing  beetles,  and  we  have  frequently  had  twigs  in  which  practically 
all  of  the  developing  beetles  were  parasitized. 


Fig.  400. — ^The  fruit-tree  bark-beetle   {Scolytus  rugulosus):  a,  b,  beetle;  c, 
pupa;  d,  larva — enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

Control. — The  most  important  point  in  the  control  of  this  and 

similar  pests  is  to  cut  out  and  de- 
stroy all  dead  and  diseased  wood. 
Burn  all  prunings  and  trimmings. 
Affected  trees  should  be  liberally 
fertilized  in  the  spring  so  that 
they  may  make  a  quick  growth 
and  better  withstand  the  in- 
jury. Repellant  washes  have 
been  advised  for  deterring  the 
beetles  from  ovipositing.  A 
thick  soap  wash  containing  a 
pint  of  crude  carbolic  acid  to  10 
gallons  may  be  used.  Professor 
Gossard  advises  whitewashing  the 
trees  in  early  spring,  again  in 
mid-summer  and  lastly  about 
October  1st,  adding  one-quarter 
pound  of  table  salt  or  some 
Portland  cement  to  make  it  more 
adhesive.  He  also  reports  killing 
the  beetles  in  their  burrows  with 
an  emulsion  of  carboKneum. 
"Emulsify  by  dissohdng  3  pounds 

Fig.  401.— Work  of  the  fruit-tree  of    naphtha    soap    in    3    gallons 

bark-beetle  showing  the  main  gal-  of  water  by  boiling.     While  hot, 

leries    the  side  or  larval  galleries,  ^^^     ^  jj^^^     ^f     carbohneum 

and  the  pupal  cells — slightly  en-  ° 

larged.     (After  Ratzeburg.)  (avenarius)    and    agitate    as   for 


478       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

kerosene  emulsion  with  a  force  pump.  Add  four  gallons  of 
water  for  use  and  apply  with  a  spray  pump.  Keep  face  and 
hands  protected  from  this  spray."  The  carbolineum  is  rather 
expensive,  however,  and  does  not  seem  to  be  much  more 
effective  than  the  whitewash. 

Control  measures,  aside  from  pruning,  are  rarely  necessary. 


The  Buffalo  Tree-hopper  * 

The  work  of  the  Buffalo  Tree-hopper  consists  of  a  series  of 
cuts  or  incisions  in  the  Umbs  of  fruit  or  shade  trees,  made  by  the 
female  in  the  process  of  egg-laying,  which  result  in  very  character- 


FiG.  402. — The  buffalo  tree-hopper  (Ceresa  bubalus  Fab.) :  a,  a,  adult,  enlarged 
and  natural  size;  twig  of  apple  showing  recent  egg-punctures  at  b;  c, 
bark  reversed  with  eggs  in  position;  d,  single  row  of  eggs — enlarged; 
e,  wounds  of  two  or  three  years  standing  on  older  limbs.  {Mter  Mar- 
latt,  U.  S.  Dept.  Agr.) 

istic  wounds.     This  injury  is  somewhat  like  that  done  by  the 

periodical  cicada  or  by  tree  crickets,  but  the  scars  are  larger 

and  are  placed  irregularly.     When  badly  attacked  the  Hmbs  of 

small  trees  sometimes  become  so  scarred  that  they  are  badly 

stunted  or  may  be  killed.     The  cause  of  this  mischief  is  a  curious 

*  Ceresa  bubalus  Fab.  Family  Membracidoe.  See  C.  L.  Marlatt,  Circular 
23,  Div.  Ent.,  U.  S.  Dept.  Agr.,  and  H.  E.  Hodgkiss,  Tech.  Bulletin  17,  N.  Y. 
Agr.  Exp.  Sta.,  p.  92. 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS  479 

little  grass-green  insect,  about  three-eighths  inch  long,  whose 
pronotum  is  broadly  expanded  into  two  sharp  horns,  which  are 
fancied  to  be  like  those  of  the  buffalo,  as  indicated  by  the  common 
name  of  the  insect.  They  are  very  common,  frequenting  all 
sorts  of  rank-growing  vegetation,  appearing  in  midsummer,  and 
being  most  numerous  in  August  and  September. 

Life  History. — Egg-laying  is  commenced  in  August  and  is 
continued  until  killing  frosts.  The  eggs  are  laid  in  two  curved  slits, 
with  from  six  to  twelve  in  each,  as  shown  in  Fig.  402,  c,  d.  In 
making  these  slits  the  female  cuts  the  bark  between  them  entirely 
loose,  so  that  the  intervening  wood  soon  dies,  possibly  to  prevent 

the  growth  of  the  wood  crushing  the 
eggs.  A  large  scar  is  thus  formed 
which  enlarges  with  each  season's 
growth,  and  finally  becomes  an  oval 
shape  by  the  center  dropping  out. 
After  a  few  years  badly  infested 
limbs    become    very   rough,    are    easily 

Fi«-     403.— Nymph    of  broken  by  the  wind  and  furnish  van- 
buffalo     tree-hopper  —  ■    ,      r        ..  ..     i        r    . 

enlarged.         (After  tage   pomts   lor   the   attack   oi    borers. 

Hodgkiss.)  Ti^g    gggs    hatch    the    next    May    or 

June.  Like  the  adults,  the  young  nymphs  feed  on  all  sorts  of 
succulent  vegetation,  seeming  to  prefer  the  juicy  annual  plants 
even  to  the  tender  terminals  of  trees,  the  orchards  suffering 
most  being  those  grown  up  in  weeds. 

Control  — By  keeping  young  orchards  well  cultivated  and  free 
from  weeds,  the  nymphs  will  have  no  food  in  early  summer  and 
will  starve  or  leave  for  better  feeding  grounds.  Patches  of  weeds 
near  young  orchards  should  also  be  destroyed.  When  trees  are 
badly  wounded  by  the  egg  punctures  they  should  be  well  pruned 
and  the  prunings  burned  to  destroy  the  eggs. 

The  Periodical  Cicada  * 

"  There  is  probably  no  insect  that  has  attracted  more  general 
interest  and  attention  in  this  country  than  the  Periodical  Cicada, 
or  the   so-called   Seventeen-year   Locust.     The   earliest   settlers 

*  Cicada  septendecim  Linn.  Family  Cicadidoe.  See  C.  L.  Marlatt,  Bul- 
letin 71,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  A.  D.  Hopkins,  Bulletin 
68,  W.  Va.  Agr.  Exp.  Sta. 


480     INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


doubtless  associated  its  vast  noisy  swarms  with  the  devastating 
invasions  of  the  Migratory  Locust  of  the  East.  Hence  the  popular 
name  locust,  which  has  been  used  so  long  that  it  is  doubtful  if  it 
will  ever  be  discarded  for  the  proper  name — Periodical  Cicada." 
They  are  quite  different  from  the  true  locusts,  or  grasshoppers, 
however,  for  the  latter  have  biting  mouth-parts  while  the  cicadas 
suck  the  juices  of  the  plant  through  a  tube-like  beak.  Some 
twenty-seven  distinct  broods  of  the  cicada  have  been  distinguished, 
seventeen  of  which  appear  at  seventeen-year  intervals  and  ten  of 
them  appear  at  thirteen-year  intervals,  the  former  being  mostly 


Fig.  404.- — The  periodical  cicada  {Cicada  septendecim  Linn.) :  a,  adult;  b, 
young  nymph — enlarged;  c,  cast  skin  of  full  grown  nymph;  d,  adult 
females  showing  ovipositor  at  b,  and  beak  at  a — natural  size.  (After 
Marlatt  and  Riley,  U.  S.  Dept.  Agr.) 

in  the  North  and  the  latter  mostly  in  the  South.  Some  one  or 
more  of  these  broods  appears  in  every  State  east  of  the  Rockies 
except  Maine,  New  Hampshire  and  Vermont.  Every  year  there 
is  a  brood  emerging  in  some  part  of  the  country,  and  the  different 
broods  have  been^carefuUy  mapped  so  that  their  emergence  may 
be  anticipated. 

Life  History. — The  adults  appear  in  immense  swarms  in  late 
May  or  early  June.  "About  four  or  five  days  after  their  first 
appearance,"  says  Dr.  Hopkins,  ''the  males  begin  to  sing," 
filHng  the  air  with  their  shrill  calls,  which  are  produced  by  two 
drum-like  membranes  on  the  under  surface  of  the  first  abdominal 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 


481 


segment.     "About  eight  or  ten  days  later  the  sexes  begin  to 
mate,  and  in  about  four  or  five  days  more  the  females  conunence 


iJ 


fiV: 


m 


Fig.  405. — Typical  cicada  injury.      Photo  bj'  W.  E.  Rumsey 

to  deposit  eggs.     Each  female  is  said  to  deposit  from  three  to 
five  hundred  eggs  in  numerous  ragged  punctures  made  by  her 


Fig.  406. — Emergence  of  cicada. 

powerful  ovipositor  in  the  twigs  of  shrubs  and  trees,  and  some- 
times in  the  stems  of  herbaceous  plants.     These  hatch  in  about 


482       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

six  or  eight  weeks  from  the  time  they  are  deposited  and  the  young 
cicada  larvse  emerge  and  fall  to  the  ground.  They  then  burrow 
beneath  the  surface  and  enter  upon  their  long  menial  existence 
in  the  ground,  feeding  on  the  Kquids  of  roots  and  possibly  sub- 
sisting on  such  nutriment  as  may  be  obtained  from  the  soil  itself. 
They  change  their  position  from  time  to  time,  and  may  rarely 
enter  the  earth  for  a  distance  of  eight  to  ten  feet  or  more,"  though 
usually  within  two  feet  of  the  surface.     "By  the  twelfth  or  thir- 


FiG.  407. — The  full-grown  nymphs  of  the  periodical  cicada  in  different  stages 
of  molting  and  the  newly  emerged  adults  with  body  and  wings  still  soft 
and  white. 


teenth  year  the  larva  attains  its  full  growth  and  in  time  changes 
to  the  intermediate  or  pupa  stage.*  During  the  spring  of  the 
fifteenth  and  sixteenth  years  great  numbers  of  the  pupae  may  be 

*  Dr.  Hopkins  and  other  writers  commonly  use  the  terms  larva  and  pupa 
in  describing  the  immature  stages  of  the  cicada,  but  there  seems  no  reason 
for  discarding  the  term  nymph  used  for  other  Hemiptera,  and  which  is  cer- 
tainly useful  in  distinguishing  the  immature  stages  of  insects  with  incom- 
plete metamorphosis  from  those  with  complete  metamorphosis  whfch  have 
a  true  pupa. 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 


483 


found  near  the  surface,  and  a  few  individuals  may  emerge  during 
May  and  June  of  the  sixteenth  year.  Early  in  April  of  the  seven- 
teenth year  the  pupie  commence  to  make  preparations  to  emerge 
from  the  ground  by  excavating  burrows  or  exit  galleries  to  the 
surface.  These  exits  are  completed  by  the 
last  of  April.  Ordinarily  they  extend  only 
to  the  surface,  and  are  kept  open  from  a 
depth  of  a  few  inches  to  a  foot  or  more. 
In  some  soils  these  exit  holes  are  extended 
four  or  five  inches  above  the  surface  by 
means  of  clay  carried  up  from  the  subsoil, 
and  are  called  cicada  chimneys.  The  pupae 
come  from  the  ground  in  the  evening  and 
at  night,  usually  between  sundown  and  ten 
o'clock,  and  proceed  to  the  nearest  upright 
object,  which  may  be  a  tree,  the  side  of  a 
building,  fence,  or  weed  stem — anything,  in 
fact,  upon  which  they  can  cHmb  and  expose 
their  bodies  to  the  action  of  the  open  air. 
In  about  an  hour  after  emerging  the  skin 
on  the  back  splits  open  and  the  adult  insect 
works  its  way  out  (Fig.  406).  The  wings, 
which  are  short  and  soft  at  first,  rapidly 
develop;  the  body,  wings  and  legs  harden, 
and  by  the  following  day  the  adult  is  ready 
to  take  flight  and  enter  upon  its  short  aerial 
life,  limited  to  about  thirty  days.  During 
this  short  period  they  feed  but  little,  if  at 
all,  the  males  devoting  their  time  during 
the  day  to  flying  about  and  making  a  noise,  ^^'^-  408.— Young  tree 
while  the  voiceless  females  busy  themselves  cloth  to  prevent  cicada 
depositing  eggs.  "  If  the  young  nymphs  do 
any  injury  to  the  roots  of  trees  or  plants, 
it  is  very  rarely  perceptible.  The  adult  females,  however,  are 
capable  of  causing  serious  injury  to  young  fruit  trees  in  orchards 
and  nurseries  by  the  numerous  punctures  in  the  twigs,  hmbs 
and  main  stems  made  by  them  in  the  act  of  ovipositing  The  egg 
puncture  makes  an  ugly  wound,  beyond  which  the  twig  dies,  and 
the  foliage  of  large  trees  on  which  hundreds  of    cicadas    have 


injun\  Photo  by  W.  E. 
Rumsey. 


484       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


M-.^.,  '^JEU-Jii 

tti^'' 

|„          ,rM^0m 

p 

h^^-  ^'M^^h^^l^m 

»;    -"^'^^ 

l^^^^i 

^^^Vr^^^ 

^M' 

Jl^oSm  'i^KH^^P 

^haT 

.  r'l^^^^^p  ■    /^]^^nk'\JSm^^^ 

jlTP^j?  ■-'^ ;." 

'iWfrNiwHifl  '  yVmOln  TrafrfT^ri 

Wt^'  '^'" 

:        '^i^^KnJgijfHMH 

^^^^v-'< 

-^^Z^HH 

w 

.-'^^Hi^il 

^^ 

Fig.  409. — Result  of  protecting  trees  with  cheese- 
cloth. Above,  protected  trees  at  end  of  the 
season;  below,  unprotected  tree  at  the  same 
time.     Photos  by  W.  E.  Rumsey. 


oviposited  turns, 
lirownasif  the  tree  had 
been  scorched  by  fire. 
On  young  trees  this 
results  in  destroying 
the  growth  of  a  year 
or  two  and  misshaping 
the  tree,  and  the  scars 
which  remain  later 
furnish  points  of  attack 
for  borers  and  the 
woolly  apple-aphis. 
Just  before  the 
cicadas  leave  the 
ground  they  are  at- 
tacked by  hogs  and 
also  by  disease.  Upon 
leaving  the  ground 
they  are  at  once 
assailed  by  a  host  of 
predaceous  insects  and 
various  animals.  One 
of  the  most  valuable 
insect  enemies  is  a 
large  wasp  (Sphecius 
speciosus  Dru.),  which 
may  often  be  seen 
bearing  the  adults  to 
its  burrow,  where  they 
furnish  food  for  her 
young.  The  English 
sparrow  is  remarkably 
fond  of  the  adults  and 
is  the  most  valuable 
factor  in  exterminat- 
ing them  in  cities  and 
towns.  It  has  been 
noticed  that  cicadas 
are  much  more  likely 
to  emerge  from  newly 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS  485 

cleared  land,  and  with  the  removal  of  the  forests  and  cultivation 
of  the  land  they  are  undoubtedly  becoming  more  scarce. 

Control. — There  is  no  means  of  destroying  the  adults,  but 
many  of  the  pupse  may  be  destroyed  by  allowing  hogs  to  run 
on  land  known  to  be  infested  during  April  and  May  of  the  year 
they  emerge,  where  it  is  feasible  to  do  so.  Injury  to  young 
orchards  may  be  avoided  by  not  planting  during  the  year  or 
two  previous  to  the  emergence  of  a  brood  in  the  particular  locality. 
Budding  and  grafting  should  also  be  avoided  during  the  previous 
spring.  Orchards  should  not  be  pruned  the  year  before  a  cicada- 
year,  so  that  there  may  be  plenty  of  young  wood  in  which  they 
may  oviposit  and  which  may  then  be  removed  without  injury 
to  the  tree.  Evidently  a  knowledge  of  the  time  of  appearance 
of  each  brood  in  different  sections  is  of  great  importance  and 
may  be  secured  from  the  maps  published  (see  Marlatt,  I.e.). 
After  all  the  eggs  are  laid  the  affected  twigs  should  be  pruned 
off  in  July  and  burned  before  the  eggs  have  hatched. 

Newly  planted  trees  may  be  protected  to  a  large  extent  by 
wrapping  them  in  cheesecloth  during  the  presence  of  the  adult 
cicadas.  The  method  has  been  tried  in  West  Virginia  and  in 
Virginia  and  the  benefits  have  been  sufficient  to  warrant  the 
necessary  expenditure. 

The  Fall  Webworm  * 

The  common  Fall  Webworm  is  so  called  because  in  the  North, 
where  there  is  but  a  single  generation,  its  webs  are  abundant  in 
August  and  September,  in  contrast  to  those  of  the  tent  cater- 
pillar, with  which  they  are  often  confused,  which  are  found  in 
the  spring.  The  wings  of  the  adult  moths  expand  from  one  to 
ll  inches,  and  are  either  a  pure  milk-white,  or  more  or  less  spotted 
with  black,  the  number  of  spots  being  exceedingly  variable.  The 
full  grown  caterpillars  are  about  an  inch  long,  covered  with  long 
black  and  white  hairs  which  project  from  numerous  black  tubercles. 
They  are  also  quite  variable  in  color,  some  being  uniformly  yellow- 
ish with  black  and  yellow  tubercles,  while  others  have  a  dark 
stripe  down  the  back  and  are  almost  black. 

Life  History. — In  the  North  the  moths  emerge  late  in  June  and 
in  July,  and  lay  the  eggs  late  in  July.  The  eggs  are  deposited 
on  the  leaves  in  pale  yellowish-green  patches  of  400  to  500,  often 

*  Hyphantria  cunea  Dru.     Family  Arctiidoe. 


486       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


covered  with  whitish  down  from  the  body  of  the  female,  and 
hatch  in  about  ten  days.  The  young  larvae  are  pale  yellowish 
with  brown  markings  and  appear  to  be  almost  all  head  and  hair. 
They  at  once  spin  a  web  over  the  foliage  on  which  they  are  feed- 
ing, those  from  one  egg  mass  feeding  together  and  enlarging  the 


Fig.  410. — The  fall  webworm  {Hyphanlria  cunea  Dru.):  a,  light  form  ,of 
full-grown  larva;  b,  dark  form  of  same;  c,  pupa;  d,  spotted  form  of 
mothball  slightly  enlarged.     (After  Howard,  U.  S.  Dept.  Agr.) 

web  as  necessary.  In  the  North  the  webs  are  usually  noticed  in 
early  August  and  are  started  at  the  tips  of  the  limbs.  Within  them 
the  surfaces  of  the  leaves  are  eaten  off  until  they  are  left  dry  and 
brown.  When  all  the  foliage  on  a  limb  has  been  consumed,  the 
caterpillars  leave  the  web,  enclosing  the  dead  leaves,  and  form  a 
new  web  on  a  fresh  branch,  and  thus  the  tree  soon  becomes  covered 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 


487 


with  unsightly  webs,  which  are  often  mingled  so  that  the  whole 
tree  is  webbed  over.     The  web  is  easily  distinguished  from  that 


Fig.  411. — Web  of  the  fall  webworm  on  apple,  showing  enclosed  foliage  and 
larvae  feeding  within. 


488       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


of  the  tent  caterpillar,  as  it  is  found  later,  and  the  tent  caterpillar 
makes  a  relatively  small  web  in  the  fork  of  a  limb  and  never 
encloses  foliage  in  it.  The  caterpillars  become  full  grown  in  a 
month  to  six  weeks,  and  then  find  secluded  places  under  the  bark 
or  in  a  hollow  of  the  tree,  in  the  rubbish  at  its  base,  or  in  a  fence 
corner,  or  sometimes  just  under  the  surface  soil,  and  there  spin 
flimsy  silken  cocoons  with  which  they  mingle  their  own  hairs. 
They  then  transform  to  small  brown  pupae  about  one-half  inch 
long,  in  which  stage  the  winter  is  passed.     In  the  Middle  States 

and  farther  south 
there  are  two  genera- 
tions, the  moths  ap- 
pearing in  April  and 
May  and  laying  eggs 
in  late  May  and  early 
June,  the  caterpillars 
from  which  becomef ull 
grown  by  mid-July. 
The  second  generation 
of  caterpillars  appears 
in  late  August  and 
September  at  about 
the  same  season  as 
farther  north,  and 
their  pupae  hibernate. 
Were  it  not  for  their 
parasitic  enemies  these 
caterpillars  would  be  much  more  of  a  pest,  and  it  is  when  the  para- 
sites become  scarce  that  injury  results.  One  of  their  most  com- 
mon and  effective  enemies  is  a  little  Braconid  fly,*  whose  small 
brown  cocoon  (Fig.  412)  is  often  found  suspended  from  a  twig  or 
leaf.  Many  caterpillars  are  also  killed  by  various  predaceous  bugs, 
and  frequently  they  are  killed  off  by  fungous  disease 

The  fall  webworm  is  a  common  pest  of  all  orchard  trees,  and 
frequently  extends  its  injuries  to  shade  trees.  The  larvae  are  not 
uncommon  on  cabbage,  beets  and  a  long  list  of  garden  crops. 
According  to  Dr.  H.  G.  Dyar  this  species  is  confined  to  the  South 

*  Meteor  us  hyphantrioe  Riley. 


Fig.  412. — Meteorus  hyphantrioe,  a  common  para- 
site of  the  fall  webworm;  a,  adult  female;  b, 
empty  cocoon  showing  cap  and  suspending  thread 
— enlarged.     (After  Riley,  U.  S.  Dept.  Agr.) 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 


489 


Atlantic  States,  but  it  has  been  confused  with  another  species 
(Hyphantria  textor  Harris)  by  practically  everyone,  and  it  is  still 
a  question  as  to  whether  the  two  species  are  really  distinct  and 
if  so  how  they  are  to  be  distinguished.  If  the  latter  form  be  a 
distinct  species,  it  occurs  throughout  the  United  States  and  has 
the  same  habits. 

Control. —  The  insect  is  readily  controlled  by  spraying  with  any 
of  the  arsenicals  when  the  work  of  the  young  larvae  is  first  noticed. 
Where  orchards  are  sprayed  for  the  codling  moth  there  will  be 
little  trouble  with  the  first  generation,  and  fruit-growers  will  do 
well  to  make  it  a  practice  to  spray  in  August  where  they  are 
troubled  with  this  and  other  leaf-eating  caterpillars. 

Mechanical  destruction  of  the 
nests  is  good  practice  when  spray- 
ing is  not  done. 


The  Brown-tail  Moth.* 
The  Brown-tail  Moth  has  become 
injurious  only  in  Massachusetts,  New 
Hampshire  and  Maine  although  it  has 
several  times  been  brought  into  other 
states  in  the  winter  nests  on  seedling 
trees  imported  from  France  and 
Belgium.  With  the  present  effici- 
ent quarantine  service  it  is  rather 
unlikely  that  it  will  become  estab- 
lished elsewhere.  On  the  contrary, 
it  seems  that  its  range  may  gradu- 
ally be  reduced  although  actual  exter- 
mination can  not  be  looked  for  in 
the  immediate  future.  It  has  long 
been  a  serious  pest  in  parts  of  central 
and  western  Europe,  whence  it  was 
introduced  into  Massachusetts  about 
attention  until  1897. 


Fig.  413. — Winter  web  of  the 
brown-tail  moth — one-half 
natural  size. 


1890,  but  did  not   attract 
The  female  moth  is  pure  white  except  the 
tip  of  the  abdomen,  which  is  golden  brown  and  forms  a  large 

*  EuprocHs  chrysorrhcea  Linn.  Family  Liparidoe.  See  L.  O.  Howard, 
Farmers'  Bulletin  264,  U.  S.  Dept.  Agr.;  E.  D.  Sanderson,  Bulletin  136,  N.  H. 
Agr.  Exp.  Sta.;  A.  F.  Burgess,  Farmers'  Bulletin  845,  U.  S.  Dept.  Agr. 


490       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


tuft  or  brush,  which  gives  the  insect  its  name.  The  wings  of  the 
female  expand  1|  inches,  the  males  being  slightly  smaller,  and  bear 
one  or  two  streaks  of  brown  on  the  under  sides.  The  full-grown 
caterpillar  is  1^  inches  long,  dark  brown,  marked  with  a  white 
dash  on  the  side  of  each  segment.  The  body  is  dark  brown 
or  blackish,  well  marked  with  patches  of  orange  and  covered  with 
numerous  tubercles  bearing  long  barbed  hairs.  On  the  centre 
of  the  fifth  and  sixth  abdominal  segments  are  small  retractile  red 
tubercles.     The  tubercles  along  the  back  and  sides  are  thickly 

covered  with  short  brown 
hairs  which  give  them  a  vel- 
vety appearance.  These 
microscopic  hairs  are 
barbed  and  are  the  nettling 
hairs  which,  when  they 
alight  on  the  skin,  produce 
a  dermatitis  much  like  that 
caused  by  poison  ivy.  As 
the  cast  skins  are  carried 
here  and  there  by  the  wind 
and  the  young  caterpillars 
drop  from  the  trees,  people 
are  frequently  badly 
poisoned  where  the  pest 
becomes  abundant,  so  that 
it  is  a  serious  public  nuisance 
as  well  as  as  defoliator  of  fruit  and  shade  trees.  The  caterpillars 
prefer  fruit  trees,  pear,  wild  cherry,  and  apple  being  most  relished, 
but  become  abundant  on  almost  all  the  common  shade  trees, 
except  the  evergreens,  and  particularly  on  oak. 

Life  History. — The  moths  emerge  in  midsummer.  They  are 
strong  fliers  and  are  readily  carried  by  the  wind  for  many  miles. 
They  are  attracted  to  lights  in  great  numbers,  so  that  they  are 
more  abundant  in  cities  and  villages.  Late  in  July  the  eggs  are 
laid  on  the  terminal  leaves,  300  or  400  being  laid  in  an  elongate 
mass  and  covered  with  brown  hairs  from  the  tip  of  the  female's 
abdomen.  They  hatch  in  about  three  weeks  and  the  young  larvae 
feed  on  the  surface  of  the  leaves,  leaving  only  the  brown  skeletons, 
so  that  badly  infested  trees  turn  brown  in  early  fall.     The  cater- 


FiG.  414. — Winter  web  of  the  brown-tail 
moth  bearing  young  larvie  which  have 
emerged  before  the  fohagehas  appeared 
and  are  feeding  on  the  dead  leaves  of 
the  nest — two-thirds  natural  size. 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 


491 


pillars  hatching  from  an  egg  mass  feed  together  on  adjoining 

leaves,  which  they  soon  commence  to  draw  together  with  silken 

threads,  and  by  the 

first  frosts  they  have 

spun    them    into    a 

tough  web.     This  is 

attached  to  the  twig 

by  the  old  leaf  stems, 

which  are  bound  to 

it  by  silk.     The  web 

looks  like  a  couple  of 

dead  leaves  from   a 

distance,    but    the 

leaves  are  merely  the 

outer  covering,  and  if 

the  silk  web  be  torn 


Fig.  415.- 


-FuU-grown   larvae  of   the  brown-tail 
moth — natural  size. 


open,  there  will  be  found  numerous  small  pellets  of  silk  each  enclos- 
ing from  three  to  twelve  of  the  little  partly'  grown  caterpillars.     The 

caterpillars  emerge  just  as 
the  buds  burst  in  the  spring 
and  feed  on  the  expanding 
foliage.  Where  abundant 
thc}^  soon  strip  a  tree,  for 
each  of  the  nests  harbors 
400  or  500  little  caterpil- 
lars. In  five  or  six  weeks 
they  have  become  full 
grown  and  spin  thin 
cocoons  of  white  silk  among 
the  leaves,  in  which  they 
transform  to  dark-brown 
pupie.  About  three  weeks 
later  the  moths  emerge. 

Several  native  parasites 
and  predaceous  bugs  prey 

_      .^„     rj^,     ,          ^  •,      j_,   ,Ti          ■  upon  the  caterpillars,  but 

Fig.  416. — The  brown-tail  moth  (Euprochs  .,                                      . 

chrysorrhfva  Linn.):  male  a]:)0ve,   female  do  not  seem  materially  to 

below— natural  size.  reduce    their     numbers. 

In  Europe  there  are  several  parasites   which  prey  on  all  stages 
of  the  insect    and  which  the  State  of  Massachusetts  with  the 


492       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


cooperation  of  the  U.  S.  Bureau  of  Entomology  is  introducing 
in  hope  that  they  may  ultimately  be  as  effective  in  this  country 

against  both  the  brown-tail  and 
gipsy  moths.  The  most  effective 
natural  check  of  the  brown-tail  cat- 
erpillar is  a  fungous  disease  which 
often  completely  destroys  large  col- 
onies, both  in  the  spring  and  fall. 

Control. — On  fruit  and  shade  trees 
the  winter  nests  may  be  pruned 
off  and  burned  in  winter,  thus  pre- 
venting any  injury  the  next  spring, 
but  this  is  impracticable  on  forest 
trees,  which  as  a  rule  are  not  seri- 
ously injured.  The  repeated  prun- 
ing often  injures  the  trees,  as  it  is 
difficult  to  cut  all  the  nests  with- 
out removing  more  of  the  new 
growth  than  is  desirable.  It  is  bet- 
ter, therefore,  to  spray  the  trees 
with  arsenate  of  lead,  4  pounds  to 
the  barrel,  as  soon  as  the  eggs  hatch 
in  late  summer,  and  thus  destroy 
the  young  larvae  before  they  have 
spun  their  winter  webs. 


■K'AJI 

fK^3t3$.f->»^ 

Fig.  417. — Brown-tail  moths  as- 
sembled on  electric  light  pole, 
Maiden,  Mass.,  July  12, 1905. 
(After  Kirkland.) 


The  Gipsy  Moth  * 

History. —  The  Gipsy  Moth  has 
been  known  as  a  serious  insect  pest 
in  Europe  from  the  time  of  the  earliest  naturalists,  the  first 
authentic  record  being  in  1662.  It  extends  throughout  the  con- 
tinent of  Europe,  over  much  of  Asia  and  into  Northern  Africa, 
but  is  chiefly  injurious  in  Central  and  Eastern  Europe.     It  fre- 

*  Porthetria  dispar  Linn.  Family  LiparidcB.  See  Forbush  and  Fernald, 
"The  Gipsy  Moth,"  Mass.  State  Board  of  Agr.  (1892);  L.  O.  Howard, 
Farmers'  Bulletin  275,  U.  S.  Dept.  Agr. ;  Annual  Reports  of  the  Mass.  Super- 
intendent for  the  Suppression  of  the  Gypsy  and  Brown-tail  Moths;  E.  D. 
Sanderson,  Bulletin  136,  N.  H.  Agr.  Exp.  Sta.;  Rogers  and  Burgess,  Bulletin 
87,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  containing  bibliography,  and 
A.  F.  Burgess,  Bulletin  204,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 


493 


quentty  does  serious  injiirj^  there  by  defoliating  large  areas  of 
forest  and  more  ferqiieutly  fruit  and  shade  trees,  but  its  ravages 
cease  in  two  or  three  seasons,  not  to  occur  again  for  several  years, 
like  those  of  many  of  our  native  insects,  such  as  the  forest  tent 
caterpillar  and  tussock  moth.  In  18G8  the  insect  was  brought 
to  this  country  by  Professor  Leopold  Trouvelot  at  Medford,  Mass., 
in  his  experiments  in  silk  producing.  Escaping  from  him  into  the 
neighboring  woodland,  the  insect  increased  gradually  for  several 
years  before  being  noticed,  but  in  1890  had  become  such  a  serious 


Fig.  418. — Gipsy  moth  caterpillars — natural  size.     (After  W.  E.  Britton.) 

pest  throughout  this  and  neighboring  towns  that  the  State  of 
Massachusetts  commenced  the  arduous  task  of  its  extermination. 
At  this  time  the  insect  occurred  in  some  twenty  towns.  For  the 
next  ten  years  it  was  successfully  combated  by  the  Massachusetts 
authorities,  and  in  1898  it  had  spread  to  but  three  towns  not 
infested  in  1890  and  in  many  places  it  had  apparently  been  exter- 
minated. So  slight  was  the  injury  that  legislative  appropriations 
were  discontinued  for  four  years,  during  which  time  the  moth 
spread  over  four  times  the  area  previously  occupied  and  became 
so  abundant  that  State  action  was  again  necessary.  From  1905 
to  1910  it  spread  throughout  eastern  Massachusetts  and  southern 
New  Hampshire  and  Maine,  and  was  found  in  two  or  three  locaL 


494      INSECT  PFSTS  OF  FARM.  GARDEN  AND  ORCHARD 


ities  in  Connecticut.*  Appropriations  for  its  control  have  been 
increased  until  now  the  State  of  Massachusetts  and  the  Federal 
Government  are  each  appropriating  $300,000  per  annum  and 
the  total  cost  of  combating  it  in  New  England  must  be  con- 
siderably over  a  milHon  dollars  per  year.  As  it  is  gradually 
spreading,  there  seems  every  reason  to  fear  that  it  may  ultimately 
invade  other  States. 

Life  History  and  Description. — The  eggs  are  laid  in  July  and 
r  -  -     -'^        August,  in  a  mass  of 

400  to  500,  covered 
with  yellowish  hairs 
from  the  body  of  the 
female.  The  mass  is 
an  irregular  ovalshape 
H  by  f  inches,  and 
is  deposited  on  the 
bark  of  trees,  but 
where  abundant,  on 
i  fences,  stones,  build- 
/  ings,  etc.  The  eggs 
hatch  about  May  1, 
and  each  mass  yields 
a  swarm  of  young  cat- 
erpillars, the  bulk  of 
I  ^  •!  which    become   full 

'  ■  — ■       -  •         —        —  grown  by  midsummer. 

Fig.  419. — The    gipsy   moth    (Porthetria    dispar  q^,  ,  ,        ■■,-, 

Linn.) :  male  above;  female  below — natural  size.    ^  "^  mature  caterpillar 
(After  Forbush  and  Fernald.)  has  a  dusky  or  SOOty- 

colored  body.  Along  the  back  is  a  double  row  of  five  pairs 
of  blue  spots,  followed  by  a  row  of^'six  pairs  of  red  spots,  which 
readily  distinguish  this  from  any  other  common  caterpillar. 
The  full-grown  caterpillar  is  about  3  inches  long.  Sometime 
in  July  or  early  August  it  spins  a  few  threads  of  silk  as  a  sup- 
port, sheds  its  skin  and  changes  into  a  pupa,  sometimes  enclosed 
in  a  thin  cocoon,    but  often  hanging   pendant   from  its  attach- 

*  Connecticut  State  authorities,  in  co-operation  with  the  Federal  author- 
ities, have  exterminated  the  insect  within  that  State. 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS  495 

ment.  Characteristic  light  reddish  hairs  are  scattered  over  the 
pupa.  The  pupal  stage  lasts  from  ten  days  to  two  weeks, 
when  the  adult  emerges.  The  moths  emerge  from  the  middle 
of  July  to  late  August.  The  male  is  brownish-yellow,  varying 
to  greenish-brown  in  color,  the  wings  being  marked  with  darker 
stripes,  has  a  slender  body  and  the  wings  expand  about  1 1  inches. 
It  flies  by  day  with  a  pecuhar  zig-zag  flight.  The  female  moth 
is  nearly  white  with  numerous  small  black  markings,  is  heavy- 
bodied  and  sluggish.  The  wings  expand  about  2  inches,  but 
fortunately  the  female  is  unable  to  use  them  for  flight.  Were  it 
not  for  this  the  spread  of  the  pest  would  have  been  much  more 
rapid.  After  mating  the  moths  hve  but  a  short  time  and  do 
no  damage. 

The  pest  is  spread  mostly  in  the  caterpillar  stage  The  young 
caterpillars  drop  down  on  fine  silken  threads  and  may  alight  on 
vehicles  which  transport  them  to  non-infested  areas.  When  just 
hatched,  the  caterpillars  have  very  long  hairs,  sHghtly  expanded 
at  the  base,  and  these,  with  the  silk  which  they  spin  out,  serve 
to  buoy  them  up  in  the  air  so  that  they  may  be  carried  for  a 
considerable  distance  by  a  strong  wind  Where  they  occur  m 
myriads  on  high  trees,  the  little  caterpillars  may  be  carried  by 
the  wind  for  considerable  distances,  and  this  is  one  of  the  chief 
means  of  spread.*  The  egg  masses  may  also  be  transported  on 
merchandise  or  boxing,  and  the  pest  has  undoubtedly  become 
established  in  several  localities  in  this  way.  A  few  cases  of 
importation  on  nursery  stock  have  been  known 

The  caterpillars  will  attack  any  of  the  fruit,  shade  or  wood- 
land trees,  and  where  they  become  excessively  abundant  will 
destroj^  all  green  vegetation  of  almost  any  kind.  It  is  essentially 
a  pest  of  forest  trees,  but  where  it  occurs  it  defoHates  all  of  the 
eonmion  fruit  trees.  Coniferous  trees  are  killed  after  being  once 
stripped  of  their  foliage,  and  deciduous  trees  usually  die  after  four 
or  five  defoliations.  Recent  experiments  show  that  the  young 
caterpillars  when  they  hatch  from  the  eggs  are  unable  to  feed  on 
conifers,  so  that  growths  of  soft  wood  may  be  protected  by  keep- 
ing all  hard-wood  trees  cut  out 

*  See  C.  W  Collins,  Bulletin  273,  U.  S  Dept.  Agr. 


496       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Control. — In  the  orcliard  the  gypsy  moth  is  readily  controlled 
by  painting  the  egg  masses  with  creosote  in  winter  and  by  spraying 


Fig.  420. — Egg  masses  of  the  gypsy  moth  on  the  trunk  of  an  apple  tree. 

the  trees  with  arsenate  of  lead,  5  pounds  per  barrel,  just  as  the 
eggs  are  hatching  in  the  spring.  Where  this  is  practiced  there 
is  very  little  trouble  in  controlling  it  in  orchards.  Upon  shade 
and  forest  trees  the  problem  is  much  more  difficult  and  the  reader 


t'.'-". 


*<»^ 


Fig.  421. — The  Calosoma  beetle  (Calosoma  sijcophanta) .  Upper  left,  eggs; 
lower  left,  adult  beetle  feeding  on  gipsy  moth  caterpillar;  upper  right, 
gipsy  moth  pupae  destroyed  by  calosoma  larva?;  center,  calosoma  larva, 
ventral  view;  right  center,  calosoma  larva,  dorsal  view;  lower  right, 
calosoma  pupa  in  cavity  in  ground.     (From  Howard  and  Fiske.) 

497 


498       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

should  consult  the  authors  cited  (footnote,  p.  492)  as  to  the  best 
means  and  apparatus.  Although  the  pest  is  still  confined  to 
New  England,  it  is  such  a  serious  one  and  there  is  so  much  danger 
of  its  spread  elsewhere,  that  fruit-growers  should  be  on  their 
guard  against  it  and  should  submit  suspected  specimens  to  the 
nearest  entomologist.  Should  it  be  found  in  any  other  States, 
no  expense  should  be  spared  to  exterminate  it  absolutely  before 
it  may  become  estabhshed. 

The  Federal  authorities,  in  addition  to  maintaining  a  rigid 
quarantine  within  the  areas  infested  by  the  gipsy-moth  and  the 
brown-tail  moth,  have  made  very  intensive  biological  studies 
of  the  insects,  both  in  this  country  and  in  its  native  home  in 
Europe  and  have  imported  from  Europe  many  of  its  natural 
enemies,  including  diseases,  hymenopterous  parasites  and  pre- 
daceous  insects  which  attack  it.  Most  important  among  the 
latter  and  possibly  the  most  important  of  the  insect  enemies,  is 
the  ground  beetle  Calosoma  sycophanta  L.,  which  is  shown  in  the 
accompanying  illustration. 

It  is  hoped  that  the  importation  of  a  large  number  of  different 
kinds  of  natural  enemies  will,  in  time,  reduce  these  insects  to  the 
status  of  native  pests  which  are  occasionally  somewhat  injurious 
but  which  are,  over  a  period  of  years,  held  in  check  b}^  the  natural 
means  of  control,  and  the  progress  of  the  work  during  the  past 
few  years  makes  it  seem  likely  that  this  will  be  accompUshed. 

Canker  Worms  * 

Since  the  early  colonial  days  Canker  Worms  have  been  among 
the  best-known  insect  pests  of  the  apple  orchard,  but  they  are 
general  feeders  and  attack  several  orchard  and  shade  trees. 
According  to  Dr.  W.  E.  Britton  they  "  seem  to  have  a 
preference  for  the  foliage  of  apple,  elm,  chestnut,  pear,  oak, 
hickory,  box-elder,  and  maple,  in  about  the  order  named,"  and 
cherry  and  plum  are  recorded  by  others.  The  canker  worms  are 
among  the  most  common  of  the  "loopers"  or  ''measuring  worms," 
and  are  the  larvae  of  two  nearly  related  species  of  moths,  very 
similar  in  both  appearance  and  habits.     The  larvae  defoliate  the 

*  Family  Geometridoe.  See  D.  W.  Coquillet,  Circular  9,  Div.  Ent.,  U.  S. 
Dept.  Agr.;  W.  E.  Britton,  Biennial  Report  Conn.  Agr.  Exp.  Sta.,  1907- 
08,  p.  777;  A.  L.  Quaintance,  Bulletin  68,  Part  II,  Bureau  of  Entomol- 
ogy, U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS  499 

trees  in  early  spring,  particularly  in  old  sod 
orchards  which  have  not  been 
cultivated  or  sprayed. 


The    Spring   Canker   Worm  * 

This  species  is  so  called  from 
the  fact  that  its  eggs  are  laid 

in  the  early  spring  instead  of  in  the  fall,  as  are 
those  of  the  other  species.  It  occurs  from  Maine 
to  Iowa  and  southward  to  Texas,  and  in  Colorado  and 
California,  but  has  not  been  reported  on  the  Atlantic 
Coast  south  of  New  Jersey  according  to  Coquillet.  It 
seems  to  be  particularly  injurious  in  the  Mississippi 
Valley.  The  full-grown  caterpillar  is  from  three- 
quarters  to  one  inch  long,  slender,  and  cylindrical, 
and  has  no  prolegs  on  the  middle  of  the  abdomen. 
The  color  varies  from  ash-gray  to  green  or  yellow, 
but  the  predominating  color  is  dark  greenish-oHve 
or  blackish,  marked  with  narrow  pale  lines  down  the 
back  and  a  whitish  stripe  along  each  side.  The  wings 
of  the  male  moths  expand  an  inch,  and  are  semi-trans- 
parent, brownish-gray,  with  three  rather  indistinct  dark 
lines  across  the  fore-wings.  The  females  are  wingless 
and  at  the  first  glance  look  much  more  like  spiders  than 
moths.  They  are  about  one-third  inch  long,  of  a  dull 
brown  or  grayish  color  with  a  dark  brown  stripe  down 
the  middle  of  the  back. 

Life  History. — The  moths  emerge  from  the  pupae  in 

the  ground  in  March  and  April  and  the  females  climb 

up  the  trunks  of  the  trees,  where  they  place  their  eggs 

in  irregular  masses  of  about  fifty,  under  loose  scales  of 

bark,  in  cracks  in  the  bark,  in  crotches  of  limbs,  etc. 

The  individual  eggs  are  yellowish-green,  turning  quite 

Fig.    422. — Canker  worms  dropping  from  foliage  in  characteristic  attitudes. 

(After  Bailey.) 

dark  just  before  the  larvse  hatch,  of  an  oval  shape,  and  about 
one-thirty-fifth  inch  long.     The  eggs  hatch  in  about  a  month  and 
the  young  caterpillars  commence  to  feed  on  the  leaves  just  as  they 
*  Paleacrita  vernata  Peck.    Family  Geometridoe. 


500,      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


are  expanding,  at  first  eating  small  holes  through  them,  but  later 


Fig.  423. — The  spring  canker  worm 
(Paleacrita  vernata):  a,  male  moth;  6, 
female  moth — both  natural  size;  c, 
joints  of  female  antenna;  d,  joint  of 
female  abdomen;  e,  ovipositor — en- 
larged.    (After  Riley.) 


Fig.  424. —  The  spring  can- 
ker worm  {Paleacrita-ver- 
nata) :  a,  larva — natural 
size;  h,  eggs — natural  size 
and  enlarged;  c,  side  view 
of  segment  of  larva ;  d ,  dor- 
sal view  of  same — both 
enlarged.    (From  Riley. 


devouring  all  but  the  midribs.    The  young  caterpillars  have  a  habit 
of  dropping  from  the  trees  and  hanging  suspended  on  strands 


Fig.  425. — The  female  moths  of  the  spring  canker  worm — twice  natural  size, 
and  pupae — three  times  natural  size.     (After  Quaintance,  U.  S.  Dept.  Agr.) 

of  silk.  In  four  or  five  weeks  they  have  become  full  grown  and 
enter  the  soil  to  a  depth  of  2  to  5  inches,  where  they  hollow  out 
earthen  cells,  which 
they  line  with  a  little 
silk  and  in  them 
change  to  pupse,  in 
which  stage  the  sum- 
mer and  winter  is 
passed.    The  pupae  is 


Fig.  426. — Eggs  of  spring  'canker  worm — twice 
natural  size.     (After  W.  E.  Britton.) 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 


501 


nearly  one-third  inch  long,  light  brown  in  color,  somewhat  pitted, 
and  the  male  pupa  bears  a  simple  spine  at  the  tip  of  the  abdomen. 

The  Fall  Canker  Worm  * 

The  Fall  Canker  Worm  seems  to  be  the  more  common  form  in 
New  England  according  to  Dr.  Britton  and  is  a  more  northern 
species  according  to  Coquillet,  occurring  through  the  North- 
Central  States  and  in  Colorado  and  northern  California.  As  its 
name  indicates,  it  differs  in  Hfe  history  in  that  the  moths  emerge 
in  November  and  December,  "often  occurring  in  great  numbers 
on  foggy  days  during  a  thaw  after  the  ground  has  been  frozen." 
They  are  most  numerous  about  the  middle  of  November  in  Con- 
necticut, although  Dr.  Britton  states  that  when  the  ground  freezes 
in  early  fall  and  does  not  thaw, 
many  of  the  adults  do  not 
emerge  until  March,  when  the 
life  history  would  be  identical 
with  the  last  species.  "The  eggs 
are  laid  in  clusters  of  about 
100,  arranged  in  rows,  each  egg 
fastened  on  end,  and  are  laid 
on  the  bark  of  the  smaller  bran- 
ches or  on  the  trunk.  The 
egg  i  s  brownish-gray,  rather 
darker  than  that  of  the  spring 


Fig.  427. — The  fall  canker  worm  {Also- 
phila  pometriaa) :  a,  b,  agg;  c,  d,  side 
and  dorsal  views  of  larval  segment — 
enlarged;  e,  egg  mass;/,  larva;  ^,  fe- 
male pupa — natural  size;  h,  anal  tub- 
ercle— enlarged.    (From  Riley.) 


species,  and  is  shaped  like  a  flower-pot,  the  outer  end  being  marked 
with  a  dark  spot  in  the  centre  and  a  dark  ring  near  the  margin. 
The  eggs  hatch  in  late  April  and  early  May  in  Connecticut.  The 
larvae  are  very  similar  in  general  appearance  to  those  of  the  spring 
canker  worm,  but  may  be  easily  distinguished  by  having  two 
pairs  of  prolegs  on  the  middle  of  the  abdomen.  The  pupa  is  sim- 
ilar to  that  of  the  other  species,  but  is  somewhat  stouter  and  the 
spine  at  the  tip  of  the  abdomen  of  the  male  pupa  is  always  forked. 
The  cocoon  is  much  tougher,  contains  more  silk,  and  is  therefore 
less  easily  crushed.  The  male  moth  is  slightly  larger  than  that  of 
the  other  species,  with  longer  antennae,  and  the  wings  are  firmer, 
less  transparent  and  darker  in  color.  The  fore-wings  are  crossed 
by  two  whitish  bands,  the  outer  one  being  indented  on  the  front 
*  Alsophila  pometaria  Harris.     Family  Geometridce. 


502       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


margin  so  that  it  forms  a  distinct  spot,  and  this  outer  band  is  seen 
on  the  hind-wings,  though  it  is  less  distinct.  The  females  are  a 
uniform,  ash-gray  without  markings,  and  with  longer  antennae 
than  those  of  the  other  species,  the  segments  of  which  are  about 
as  broad  as  long,  and  are  bare  of  hairs. 

Control. — In  old  sod  orchards  where  the  pest  is  always  worst 
thorough  cultivation  will  largely  destroy  the  pupae  during  the  sum- 
mer. The  caterpillars  may  be  quickly  de- 
stroyed by  spraying  with  arsenate  of  lead, 
3  pounds  per  barrel.  The  first  spray- 
ing should  be  apphed  as  soon  as  the 
foliage  is  fairly  expanded  and  before  the 
trees  bloom,  and  the  second  should  be 
given  as  soon  as  the  blossoms  drop. 
The  first  is  the  more  important  and  one 
thorough  spi^aying  will  usually  suffice,  as 
the  young  caterpillars  are  much  more 
easily  killed .  Where  for  any  reason  spray- 
ing is  not  feasible,  the  females  may  be 
prevented  from  ascending  the  trees  by 
encircling  the  trunks  with  bands  of  tangle- 
foot or  someother  sticky  substance  which 
they  cannot  cross.  These  bands  should 
be  applied  in  early  October  and  late 
March,  according  to  the  species  preva- 
lent. The  tanglefoot  may  be  apphed 
directly  to  the  bark  of  the  tree,  making 
a  band  two  inches  wide  by  one-quarter 
inch  thick.  Printer's  ink,  bodlime,  and 
caterpillar-lime  are  often  used,  but  should 
not  be  placed  on  the  bark.  A  narrow 
band  of  cotton  batting  should  be  run  around  the  tree  and  cov- 
ered with  a  strip  of  building  paper  4  to  6  inches  wide,  on  the 
center  of  which  the  sticky  band  should  be  placed,  thus  preventing 
any  injury  to  the  bark  by  the  material.  Where  sprajdng  and  cul- 
tivation are  customary  canker  worms  rarely  become  troublesome, 
but  they  are  likely  to  be  the  worst  insect  pest  of  street-trees  and 
wood-lots  in  the  Middle-west. 


Fig.  428.— Wingless  fe- 
male moth  and  egg 
mass,  and  winged  male 
moth  of  the  fall  canker 
worm  —  twice  natural 
size.  (  A  f  t  e  r  W.  E. 
Britton.) 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 


503 


The  Evergreen  Bagworm  * 

The  Bagworm  is  more  frequently  considered  as  a  shade-tree 
pest  than  as  an  orchard  enemy.  At  the  same  time  its  possi- 
bihties  for  injury  in  the  orchard  are  of  great  importance.  We 
have  seen  apple  orchards  with  many  trees  killed  in  a  period 
of  two  years  and  in  oiu^  iiistniuu^  in  Kansas  a  ninety-acre  orchard 


Fig.  429. — Canker  worm  iiiu.ii.,  auJ  egg  masses  caught  on  stiekv  l<and. 
(After  W.  E.  Britton.) 

was  abandoned  because  the  insect  had  injured  most  of  the  trees 
bej'^ond  recovery.  The  bagworm  feeds  on  evergreens  such  as 
juniper  or  red-cedar  and  arborvitae  as  well  as  on  fruit  and  shade 
trees.  It  attacks  locust,  maple,  poplar,  apple,  plum  and  many 
other  trees,  showing  a  preference  for  the  evergreens  and  the 
locust. 

*  Thyridopteryx  ephemeroeformis  Haw.  Family  Psychidae.  See  Howard 
and  Chittenden,  Farmers'  Bulletin  701,  U.  S.  Dept.  of  Agr.,  and  L.  Haseman, 
Bulletin  104,  Missouri  Agr.  Expt.  Station. 


504       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


It  is  a  native  insect  and  is  found  generally  over  the  country- 
east  of  the  Rockies  and  south  of  the  northern  tier  of  States,  but 
injury  is  most  serious  in  the  Central  States. 

Injury  is  usually  sporadic,  occurring  for  a  year  or  two  and 
then  disappearing.  This  is  due  to  the  subjection  of  the  insect 
by  its  many  parasites  which  keep  it  from  being  at  all  times  a 
first-class  pest. 

The  male  moth  is  a  small,  black  form  with  short,  rounded, 
clear  wings  and  is  rarely  seen.     The  female  is  wingless  and  does 


Fig.  430. — Bagworm,  Thyridoptenjx  ephemeroeformis:  a,  larva;  b  and  c,  pupa, 
side  and  back  views;  d,  adult;  e,  case  containing  the  eggs;  /,  larva  in 
case;  g,  eggs.     Natural  size.     (After  Forbes.) 

not  leave  the  bag  or  cocoon.  In  this  cocoon,  in  the  fall,  she  lays 
her  eggs  and  in  this  state  the  winter  is  passed.  In  early  spring 
the  eggs  hatch  and  the  young  larvae  feed  on  foliage,  forming 
almost  immediately  their  bags  or  cocoons  which  they  enlarge  as 
they  grow.  The  cocoons  are  first  the  shape  of  tiny  cones  which 
project  from  the  upper  surface  of  the  leaves  upon  which  the  insects 
are  feeding  and  conceal  all  but  the  head  and  feet  of  the  worm. 
When  the  insect  is  nearly  grown  it  begins  to  taper  the  lower  end  of 
the  cocoon  and  by  the  time  growth  is  completed  the  cocoon  tapers 
about  equally  toward  each  end,  being  spindle-shaped.  It  is  at- 
tached firmly  by  a  band  of  silk  to  a  small  twig  and  the  larva  pup- 
ates. Males  emerge  in  a  few  weeks  but  the  females  remain  in  the 
bags  and  produce  their  eggs. 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 


505 


Control  is  accomplished  by  spraying  with  arsenate  of  lead, 
apphed  at  the  time  of  the  first  appearance  of  the  foliage  as  for 
the  curcuho  and  canker-worms. 


The  Plum  Curculio  * 

Throughout  the  States  east  of  the  Rocky  Mountains,  the  Plum 
CurcuUo  is  one  of  the  worst  pests  of  the  common  stone  and  pome 
fruits.  Its  larva  is  the  common 
white  "worm"  found  in  peaches, 
plums,  and  cherries,  while  apples 
and  pears  are  scarred  and  gnarled 
bj'  the  feeding  and  egg  punctures 
made  by  the  adults.  It  is  a 
native  insect  which  breeds  on  wild 
plums,  wild  crab-apples  and  haw- 
thorns. The  adult  is  a  thick-set 
snout-beetle  about  one-quarter 
inch  long,  brownish  in  color, 
marked  with  gray  and  black, 
and  with  four  black  ridged  tuber- 
cles on  the  wing-covers.  The 
larva  is  a  footless,  cylindrical, 
whitish  grub,  about  one-third  inch 
long,  with  a  small  brown  head, 
and  usuall}^  hes  in  a  curved  position  as  in  Fig.  432. 

Life  History . . — The  beetles  hibernate  under  grass,  leaves,  and 
other  trash  on  the  ground  in  or  near  the  orchard,  or  in  neighboring 
woodlands,  and  commence  to  emerge  just  before  the  fruit  trees 
bloom  in  the  spring.  They  feed  somewhat  on  the  buds,  unfolding 
leaves  and  blossoms,  but  mostly  on  the  young  fruit  as  soon  as  it 
is  set;  indeed,  in  New  England  the  beetles  do  not  emerge  until 
a  week  or  two  after  the  apple  blossoms  fall.  The  females  com- 
mence to  lay  eggs  in  the  young  fruits  as  soon  as  formed.  The 
egg  puncture  of  the  plum  curculio  is  shaped  Hke  a  crescent  and 

*  Conotrachelus  nenu'phar  Herbst.  Family  Curculionidoe.  See  C.  S. 
Crandall,  Bulletin  98,  111.  Agr.  Exp.  Sta.;  S.  A.  Forbes,  Bulletin  108,  ibid.; 
J.  ]M.  Stedman,  Bulletin  64,  Mo.  Agr.  E.\p.  Sta.;  E.  P.  Taylor,  Bulletin  21, 
Mo.  State  Fruit  Exp.  Sta.;  A.  L.  Quaintance,  Yearbook  U.  S.  Dept.  Agr., 
1905,  p.  325;  Circular  120,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  and 
Bulletin  103,  ibid. 


Fig.   431.  —  Bagworm   cocoons 
or  "  Bags." 


506       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


has  given  it  the  very  apt  name  of  "  little  Turk."  The  female 
first  eats  out  a  small  hole  with  her  stout  snout,  and  deposits 
a  small,  oval,  white  egg  in  the  cavity.     She  then  cuts  a  small 

segment  of  the  skin 
and  flesh  around  it  so 
that  the  growth  of  the 
fruit  will  not  crush  the 
egg,  the  whole  opera- 
tion taking  from  fifteen 
to  thirty  minutes.  The 
Ufe  of  the  female  aver- 
ages about  two  months, 
during  which  time  she 
will  lay  100  to  300  eggs 
and  probably  make  as 
many  more  feeding 
punctures.  The  punc- 
tures made  by  the  adults  of  both  sexes  in  feeding  are  simple 
round  holes  like  those  in  which  the  eggs  are  laid,  but  without 


Fig.  432. — The  plum  curculio  {Conotrachelus 
nenuphar  Herbst.):  a,  larva;  b,  beetle;  c, 
pupa — all  much  enlarged.  (After  Chitten- 
den, U.  S.  Dept.  Agr.) 


1  2 

Fig.  433. — 1,  young  plums  showing  crescent-shaped  egg  punctures  of  the 
plum  curculio;  2,  adult  curculio  on  young  peach — four  times  natural 
size.     (After  Quaintance,  U.  S.  Dept.  Agr.) 

the  crescent  marks.    Frequently  gum  exudes  from  punctures  on 
the  stone  fruits. 

The  egg  hatches  in  from  three  to  five  days  and  the  young 
larva  bores  into  the  fruit  until  grown,  usually  feeding  around  the 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 


507 


pit  in  stone  fruits.     The  larva  becomes  grown  in  from  twelve  to 
eighteen  days  (in  peaches)  according  to  Quaintance,  but  in  cen- 


FiG.  434. — Plum  curculio  on  young 
apple  and  egg  punctures  —  en- 
larged. 


Fig.  435. — The  plum  cur- 
culio —  enlarged  five 
times.    (After  Stedman.) 


tral  Illinois  in  fallen  apples  it  requires  from  twenty  to  twenty-six 
days  according  to  Crandall.     When  full  grown  the  larva  leaves 


Fig.  436. — Larvae  of  the  plum  curculio — enlarged  five  times.   (After  Stedman.) 

the  fruit  and  enters  the  soil,  where  it  forms  a  small  cell  an  inch 
or  two  below  the  surface,  in  which  it  transforms  to  a  white  pupa. 
Three  or  four  weeks  elapse  before  the  emergence  of  the  adult 


508       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


beetles;  the  first  emerge  about  ten  weeks  after  the  apples 
blossom,  the  majority  appear  two  or  three  weeks  later,  and  the 
rest  continue  to  emerge  until  October.     If  the  weather  is  dry 

the  beetles  may  remain  in  the 
cells  much  longer  than  normally, 
while  a  shower  will  bring  out 
numbers  of  them.  Upon  emerg- 
ing the  beetles  feed  upon  the 
ripening  fruit.  In  many  sections 
the  injury  to  apples  by  the  feed- 
ing punctures  then  made  is  worse 
than  the  spring  injury,  as  the 
surface  of  the  fruit  is  injured 
and  entrance  places  for  rot  are 
furnished.  The  beetles  average 
about  one  puncture  a  day  for  six 
weeks  after  emergence  in  central 
Illinois  and  commence  to  enter 
hibernation  with  the  first  frosts. 
In  New  Hampshire  we  have 
seen  no  evidence  of  injury  by 
the  beetles  in  late  summer  or 
fall. 

Injury. — Injured  plums  and 
peaches  usually  drop  to  the 
ground,  or  if  they  remain  on 
the  tree,  ripen  prematurely, 
and  rot  more  quickly.     Cherries 

,  ,      stick  to  the  tree,  but  the  fruit  is 

Fig.  437. — Work  of  the  plum  curculio      .,  n       i  i    i  ^         .i 

on  apple:  d,  feeding  punctures  from  often  small  and  gnarled  from  the 
surface  and  in  section;  e,  egg  punc-  egg-SCars,  or  eaten  O  U  t  by  the 
ture  from  surface;  e.,  same  m  sec-   ,  _  i      ,,      i  i 

tion— all  enlarged.  (After  C.  S.  larva.  In  apples  the  larvse  only 
Crandall.)  develop  in  those  which  drop  to 

the  ground,  the  rapid  growth  of  the  apples  probably  crushing  the 
eggs.  The  egg-scars  and  feeding-punctures  cause  apples  to  be- 
come gnarly,  this  being  particularly  true  of  summer  varieties,  which 
are  often  rendered  worthless,  and  even  winter  sorts  are  blemished 
by  the  scars  which  also  furnish  points  of  attack  for  rots. 


INSECTS  INJURIOUS  TO  ORCHARD  FRUITS  509 

Control. — Frequent  cultivation  while  the  pupsB  are  in  the  soil 
in  midsummer  will  throw  them  to  the  surface  and  crush  many  of 
them,  and  has  been  found  to  aid  materially  in  the  control  of  the 
pest.  As  the  larv  often  develop  in  the  fallen  fruit,  it  is  well 
to  gather  it  every  few  days  and  destroy  it  before  the  larvae  have 
left  it  to  pupate,  which  will  also  aid  in  the  control  of  other  fruit 
pests.  The  beetles  have  a  habit  of  "sulling,"  "playing  possum," 
or  feigning  death,  when  suddenly  disturbed,  and  will  drop  to  the 
ground  if  a  limb  is  jarred.  This  has  given  rise  to  the  common 
practice  of  jarring  peach,  plum,  and  cherry  trees  and  collecting 
the  beetles  on  frames  beneath  them.  This  may  be  done  with 
simple  frames  covered  with  canvas,  a  frame  being  placed  on  either 
side  the  tree  and  a  flap  extending  from  one  over  the  edge  of  the 
other,  from  which  the  beetles  are  picked  up,  or  a  regular  curcuHo- 
catcher  such  as  has  been  commonly  used  in  New  York  may  be 
more  convenient.  This  is  used  as  shown  in  Fig.  438,  the  frame 
being  covered  with  oil-cloth  and  slanting  to  a  can  containing  kero- 
sene for  the  destruction  of  the  beetles  which  slide  into  it.  The 
jarring  should  be  done  in  the  morning,  as  the  beetles  do  not  drop 
as  readily  in  midday. 

The  jarring  method  of  curculio  control  has,  at  the  best.,  merely 
a  historical  interest  now  as  it  is  impractical  in  commercial  orchards 
and  of  doubtful  value  elsewhere. 

Modern  methods  for  curculio  control  are  based  on  the  feeding 
habits  of  the  adults.  Since  these  feed  on  the  young  foliage 
in  the  spring  before  and  during  the  egg-laying  period  they  may 
there  be  poisoned.  Arsenate  of  lead  is  the  material  most  largely 
used,  the  appKcations  on  apple  as  recommended  for  the  codhng 
moth  giving  fair  control.  If  curcuHo  injury  is  more  serious,  there 
should  be  a  spray  appUed  to  the  apples  before  the  blossoms 
open.  This  is  known  as  the  "cluster-bud"  spray  and  is  often 
necessary  for  canker-worm  control  as  well  as  advisable  for  certain 
diseases.  On  peach,  plum  and  cherry,  the  time  of  application 
is  varied  to  some  extent,  but  if  one  bears  in  mind  that  it  is  well 
to  keep  the  foliage  covered  with  poison  from  the  time  it  appears 
in  the  spring  for  a  period  of  about  six  weeks  and  arranges  the 


510        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


spray  schedule  so  as  to  accomplish  this  as  nearly  as  possible,  he 
will  secure  satisfactory  control  of  the  curculio. 

Arsenate  of  lead  must  be  applied  with  care  to  the  peach  as 
the  foliage  is  tender.  It  is  frequently  apphed  with  self- 
boiled  lime-sulphur  and  if  this  is  not  used  hme  should  be 
substituted 

The  Oriental  Peach  Moth  or  Fruit  Moth  * 

Another  recent  importation  from  the  Orient  which  deserves 
mention  on  account  of  its  almost  unUmited  possibiUties  for  evil 


Fig.  438. — Jarring  trees  over  a  curculio  catcher.     (After  Slingerland.) 

is  the  so-called  Oriental  Fruit-moth  or  Peach-moth.     It  is  closely 

related  to  the  codling-moth  but  is  more  difficult  to  control  as 

it  has  four  to  six  broods  each  year  and  it  feeds  on  foUage,  in  fruit 

and  in  the  twigs,  its  feeding  habits  being  such  that  effective 

control  by  means  of  spraying  would  be  impossible. 

This  insect  has  been  noticed  in  the  District  of  Columbia  and 

has   since   been   found   in   Maryland,    Virginia,    West   Virginia, 

*  Laspeyresia  moelsta  Busk. "  Family  Tortricidoe.  See  Philip  Carman, 
Bulletins  209  and  223,  Md.  Agr.  Expt.  Station,  and  Quaintance  and  Wood, 
Jour.  Agr.  Research,  Vol.  VII,  No.  8,  and  Wood  and  Selkregg,  ibid,  Vol. 
XIII,  No.  1. 


Fig.  439.— Work  of  Oriental  fruit,  moth:  a,  characteristic  wilted  tip;  h,  twig 
cut  open  showing  larva  in  burrow.     (.After  Wood  and  Selkregg,  1.  c.) 

511 


512        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


and   neighboring   states. 


It  has  not  developed  in  abundance 
except  in  and  near  the  District  of 
Columbia  as  yet  and  it  is  possible 
that  it  will  find  some  conditions  here 
which  will  tend  to  discourage  its  wide 
spread. 

The  larvsB  are  similar  to  the  cod- 


Fig.  440.— Adult  Oriental  fruit 
moth.  After  Wood  and  Sel- 
kregg,  Ic. 


Fig. 


441. —  Oriental    fruit    moth    larva, 
After  Wood  and  Selkregg,  I.e. 

ling  moth  but  may  be  distinguished  by  food  habits  which  have 
been  mentioned  The  moth  is  the  size  of  the  codling  moth  but  a 
duller  and  more  uniform  gray  in  color. 

Control  measures  have  not  yet  been  determined. 


SPRAY5CHEDULE 
for  APPLES 


(  NORTHERN  STATES ) 


.  San  Jose 
scale  , 


Opening  bud 
taininy  bud- 
moth  larva  Note 
s  ejected 
at  tip, 


I.The  DORMANT  SPRAY 

Use  linne-sulphurconcentrate(lg-al.to7or8  gals, 
of  ■water)inlate  fall. durui?- ■warm  days  of  winter, 
or  in  early  sprm^gde/bre  the  leaf  buds  are  open . 
This  IS  for  5anJose'5cale  and  other  scales. 

Where aphids  are trouhlesome  add  J^pt.of  40% 
nicotine  sulphate  to  every  SOg^ls.  of  spray  and 
delay  application  till  buds  are  just  showing- 
green  but  not  till  tips  of  leaves  separate.  Or 
make  a  special  treatment  for  aphias  \vith  nico- 
YoungdjjtikiMtin  tine sulphateCMpt.toSOg-ab.of  water  in  whicK^ 
''^ ''^'"'^^ '"^*- 5  or  libs  of  6oap  have  been  dissolved ). 
Where  leaf-rollers  are  particularly  troublesome  add  3  lbs  of  powdered 
arsenate  of  lead(or61bs.of  the  pasteform)toeveiy  50g-als.oflime-sul-      Achidson 
phur  andspray  as  directed  for  aphids.  (When  nicotine  isused  with  lime-    openinc-iud 
sulphurob/jo^ti'j'e.yoa/i.)  Or.inplaceoftheabovesprays, use  kerosene 
emula  ion  or  a  raiscible  oil  for  scales,  aphicb  amd  leaf-roller  effys- 

II.  FIRST  SUMMER  SPRAY 
\        Use  lime-sulphur  concentrate 
-  1  (IVig-aJs  to50g-als.ofvvater)and 

/Hi),  of  powdered  arsenate  of  lead    Apptredbujs 
,    (or21bs.ofthepastefGrm)ineve)y    and  injury  to  fruit 
T>mefor  sprayll.   ^0  gals,  of  Spray  >j^  before  the  blossoms  open. 

'^   ■'  I  his  spray  IS  for  bud-moth, leal-roller.tent  caterpillars, 

cankerworms,plumcurculio,andsoab. 

Where  apple  red  bug-s  are  troublesome  add  nicotine 

Codlinemoth  ^^'"^     sulphate('/^ pt.toeverySOg-alsof spray). This grives 

]p\     also  further  protect  ion  against  aphids. 

-Vy^       Where  bud-moth  and  leaf-roller  are  especially 

"-^^  troublesome  use  .3  lbs.  of  the  powdered  arsenate 

(oT  6  lbs  of  the  paste  form)  to  eveiy  50  g'als.of  spray 

and  apply  iv/ien  the  blojsom  duds  are  first  in  evidence. 


<a*^. 


Injury 

by  secorid 

brood  of  codling- moth. 


III.  SECOND  SUMMER  SPRAY 

Usesame  spray  as  in  II  just  after  the  petals  have 
fallen  hut  before  the  calyx  lobes  have  closed. 

This  spray  is  for  same  pests  as  in  II  and  is  the 
most  important  spray  iorscab  and  CODLING 
ViOTW.Special  care  Should  be  taken  to  drive  the 
poison  into  the  opfn  calyx  cups  because  the 
majority  of  the  codling-moth  larveecf  thefir^t 
broodwill  enterthe  apples  througbthecatyxend. 

If  apple  red  bug-s  are  still  troublesoi-ne  add 
nicotine  sulphate  as  in  II.  . 

IV.  THIRD  SUMMER  SPRAY 
Use  same  spray  as  inll  three  or  four  weeks  after  the  petals 
have  fallen  for  same  pests  as  before  and  for  leaf-spot. 

V.  FOURTH  SUMMER  SPRAY  \ 

Use  same  spray  as  in  11 ,  eig-ht  or  nine  v^reeks  after 
the  petals  have  fallen, for  second  brood  of  the  cod- 
ling- motK  and  for  acab;  or  use  Bordeauix  mix- 
ture (3"  3  "50)  in  place  of  lime-sulphur,espec- 
ially  If  blotch  and  bitter- rot  are  present. 


EffecCofplumcur- 
culio  on  applet  at 
picking-  time. 


For-  /lill  infoi 


.  seerAIiM£:RS'B!yJLI-ETlN--l-S£.U-S  D  A.. 


FiQ,  442. — Apple  spraying  chart.     Bureau  of  Entomology,  U.  S.  Dept.  Agr. 

513 


CHAPTER  XXV 

INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 

The  Woolly  Apple-aphis  * 

The  Woolly  Aphis  is  one  of  the  most  destructive  pests  of 
young  apple  orchards,  and  as  it  works  mostly  upon  the  roots  it 
often  escapes  detection  until  the  tree  is  badly  injured  or  killed. 


Fig.  443. — ^The  woolly  apple-aphis  {Eriosoma  lanigera  Hausm.):  a,  agamic 
female;  h,  young  nymph;  c,  last  stage  of  nymph  of  winged  aphis;  d, 
winged  agamic  female  with  enlarged  antenna  above — all  greatly  enlarged 
and  waxy  excretion  removed.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

The  aphids  will  be  found  clustered  in  bluish-white,  cottony 
masses,  looking  Hke  patches  of  mold,  on  the  smaller  twigs,  par- 
ticularly water-sprouts,  and  around  wounds  or  scars  on  the  trunk 

*  Eriosoma  lanigera  Hausmann.  Family  Aphididce.  See  C.  L.  Mar- 
latt, Circular  20,  Div.  Ent.,  U.  S.  Dept.  Agr.;  R.  I.  Smith,  Bulletin  23,  Ga. 
State  Board  of  Ent.;  Gillette  and  Taylor,  Bulletin  134,  Colo.  Agr.  Exp.  Sta., 
p.  4;  C.  P.  Gillette,  Journal  of  Economic  Entomology,  Vol.  I,  p.  306;  A.  C. 
Baker,  Report  101,  U.  S.  Dept.  Agr.,  and  B.  R.  Leach,  Bulletin  730,  U.  S. 
Dept.  Agr. 

514 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR        515 


or  limbs.  Their  presence  in  these  places  is  always  an  indication 
that  others  are  feeding  upon  the  roots,  where  they  cause  gall-Uke 
swellings,  so  that  the  roots  soon  become  a  mass  of  knots  and  die 
in  a  year  or  two  if  the  injury  continues.  When  badly  attacked 
a  tree  becomes  sickly,  the  foliage  turns  yellow,  and  if  not  killed 
outright  by  the  aphids,  it  falls  an  easy  prey  to  borers  and  other 
pests.  Injury  seems  to  be  worse  on  light  soils  and  not  so  severe 
on  heavy  soils.  Whether  the  insect  is  a  native  or  a  European 
species  is  a  matter  of  dispute.  In  Europe  it  is  called  the  "Amer- 
ican blight,"  and  was  described  from  Germany  in  1801.  It  has 
now  become  distributed  all  over  the  world  on  nursery  stock, 
which  forms  the  principal  means  of  its  dissemination. 


Fig.  444.^The  woolly  apple-aphis:  at  left,  apterous  viviparous  female;  10, 
fall  migrant;  11,  over-winter  young.     (After  Gillette  and  Taylor.) 

Life  History. — On  infested  trees  aphids  will  be  found  in  all 
stages  of  growth  on  the  roots  in  early  spring.  On  the  trunk, 
under  bits  of  bark  or  under  the  dead  bodies  of  those  killed  the 
previous  fall,  will  be  found  numerous  small  aphids  which  have 
hibernated  there,  though  in  the  North  these  may  be  killed  out 
during  severe  winters.  As  the  buds  begin  to  open,  the  aphids 
on  the  trunk  locate  on  tender  new  bark  and  commence  to  feed, 
and  many  migrate  from  the  roots  to  the  top  at  about  the  same 
time  They  are  not  usually  detected  until  they  have  multiphed 
sufficiently  to  make  small  white  patches,  on  the  bark  or  leaves, 
which  look  hke  mold.  During  the  spring  and  summer  all  are  wing- 
less females,  not  over  one-tenth  inch  long,  of  a  reddish-brown 


516        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


color  and  covered  with  a  white,  waxy  secretion,  given  off  in  threads 
from  the  abdomen  so  as  to  form  a  cottony  mass  over  the  colony. 
These  females  produce  from  2  to  20  young  per  day,  which 
become  full  grown  in  from  eight  to  twenty  days  according  to 
Alwood,*  100  or  more  probably  being  produced  in  two  weeks. 


Fig.  445. — The  woolly  apple-aphis:  at  left,  colonies  on  twig  and  in  scar 
on  an  apple  limb;  at  right,  crown  and  root  of  young  apple  tree,  showing 
characteristic  swellings  produced  by  the  root  aphids.     (After  Alwood.) 

Reproduction  continues  on  both  tops  and  roots  except  as  checked 
by  the  cold  of  winter,  the  aphids  becoming  most  abundant  in 
midsummer.  Early  in  the  fall  a  generation  of  winged  aphids 
appears,  which  migrates  to  other  trees.  They  are  about  one- 
twelfth  inch  long  and  have  a  wing  expanse  of  one-quarter  inch. 
They  appear  to  be  black,  but  the  abdomen  is  really  a  dark  yel- 
lowish or  rusty  brown  color  when  closely  examined,  and  bears 
more  or  less  of  the  waxy  secretion  on  the  tip.  Each  of  these 
winged  females  gives  birth  to  from  four  to  six  wingless  males  and 

*  Bulletin  45,  Va.  Crop  Pest  Commission,  p.  12,  Special  Bulletin,  Va. 
Agr.  Exp.  Sta. 


n 


Fig.  446. — Woolly  apple-aphids  on  stem  of  seedling  tree  and  swellings  made 
on  roots  slighth-  enlarged.     (After  Rumsey  and  Brooks.) 

517 


518        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


females,  which  are  deposited  on  the  trunk  of  the  tree.  The 
sexes  are  wingless,  much  smaller  than  the  summer  forms,  and 
are  without  beaks,  so  that  they  take  no  food.  The  female  is 
a  brown-ochre  color,  and  the  male  dark  green  or  greenish- 
brown  and  smaller,  as  shown  in  Fig.  448.  They  become  full 
grown  in  about  eight  days,  when  they  mate  and  the  female  then 


Fig.  447. — Sexual  female  of  the  woolly  apple-aphis,  showing  egg  before  and 
after  extrusion — greatly  enlarged.     (After  Alwood.) 

lays  a  single  large  black  egg,  which  is  deposited  in  the  crevices 
of  the  bark  on  the  lower  part  of  the  trunk.  These  eggs  hatch 
in  the  spring  and  give  rise  to  new  colonies. 

As  they  multiply  large  galls  are  produced  on  the  roots,  the 
tissue  probably  being  poisoned  by  the  mouth-parts  of  the  insects. 
As  a  result  the  roots  soon  die  and  the  aphids  then  migrate  to 
the  growing  roots,  so  that  their  absence  on  the  worst  knotted 
roots  does  not  indicate  that  they  have  forsaken  the  tree  but  that 
they  are  on  younger  roots. 

Control. — Nurserymen  commonly  apply  a  liberal  amount  of 
tobacco  dust  in  trenches  along  the  rows,  which  kills  the  aphids 
and  acts  as  a  repellant,  as  well  as  being  worth  half  its  cost  as  a 
fertilizer.  This  is  probably  the  best  practice  in  the  nursery  unless 
the  aphids  become  abundant  when  more  vigorous  treatment 
should  be  used,  but  tobacco  has  not  always  proven  a  satisfactory 
treatment  for  orchard  trees   though  used  with  apparent  success 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR       519 

in  some  instances.  The  aphids  may  be  destroyed  on  the  fohage 
by  spraying  with  7  per  cent  kerosene  emulsion,  miscible  oils 
diluted  30  to  40  times,  whale-oil  soap,  1  pound  to  6  gallons,  or 
tobacco  extracts,  "black  leaf -40"  being  used  1  part  in  700  of  water. 
Whatever  insecticide  is  used  must  be  applied  in  a  strong  spray 
so  as  to  wet  thoroughly  and  penetrate  the  waxy  covering  of  the 
aphids.  A  winter  spray  of  Ume-sulphur  wash  destroys  the  hiber- 
nating aphids  on  the  trunk, 
and  doubtless  kerosene 
emulsion  or  miscible  oils 
applied    in    early    spring, 

as  for  the  San  Jose  scale, 
would  be  as  effective, 
though  the  Ume-sulphur 
would  probably  also  de- 
stroy some  of  the  eggs. 
The  trunks  of  trees  known 

to    be    infested     may     be  Fig.    448.— Sexual  female  and    male    of   the 
banded     with      tanglefoot       ^PP^^y   apple-aphis  — greatly    enlarged. 

.     .,  , .  ,  ,  (After  Alwood.) 

or  similar  sticky  mater- 
ials as  described  for  canker  worms  (p.  502)  to  prevent  the 
aphids  from  migrating  from  the  roots  to  the  top.  Where 
the  aphids  are  abundant  on  the  roots,  the  earth  should  be 
removed  for  6  or  8  inches  deep  over  the  affected  roots  and 
Ume-sulphur  solution,  diluted  about  one  to  eight,  appUed  in 
quantities  sufficient  to  wet  the  soil  thoroughly  about  the  roots. 
Other  solutions  tried  for  soil  treatment  have  given  less  success 
than  this. 

Some  success  has  been  reported  by  Leach  from  the  use  of 
carbon  disulphide  in  water  solution,  one  ounce  to  four  gallons, 
appUed  about  the  roots  with  a  power  sprayer.  Sodium  cyanide 
solution,  appUed  in  the  same  way  also  gave  fairly  good  results. 
With  any  of  these  methods  there  is  the  disadvantage  that  they 
require  large  quantities  of  water  to  be  transported  to  the  orchard 
and  all  are  somewhat  expensive. 

Liberal  fertilization,  to  enable  the  tree  to  do  well  in  spite 
of  the  presence  of  the  aphids  is  probably  more  practical  for  most 
growing  conditions. 


520        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Round-headed  Apple-tree  Borer  * 

The  young  apple  orchard  must  be  given  frequent  inspection 
to  detect  the  work  of  the  round-headed  borers,  for  if  they  become 
estabhshed  in  the  young  trees  it  is  difficult  to  kill  them  and  they 
soon  girdle  the  trunks.  They  are  most  injurious  to  apple  and 
quince,  less  so  to  pear,  and  also  infest  wild  thornapple  trees  and 
mountain  ash.  The  species  occurs  generally  east  of  the  Rocky 
Mountains,  but  is  not  commonly  injurious  in  the  Gulf  States. 
The  presence  of  the  borers  may  be  detected  by  the  retarded  growth 


Fig.  449. — The  round-headed  apple-tree  borer  (Saperda  Candida  Feb.)  larvse, 
adults,  and  exit  holes — natural  size.     (After  Rumsey  and  Brooks.) 

of  the  trees,  with  a  yellowing  of  the  foHage,  and  the  sawdust  hke 

castings  which  the  larvse  throw  out  from  the  entrances  of  their 

burrows,  accompanied  by  a  discoloration  of  the  bark  over  the 

new  burrows,  and  in  early  spring  there  is  often  a  slight  exudation 

of  sap.     Injury  is  most  severe  in  neglected  orchards,  where  grass 

and  weeds  are  allowed  to  grow  about  the  bases  of  the  trees,  as 

the  beetle,  which  flies  at  night,  seeks  the  concealment  of  the 

rank  vegetation  during  the  day.    The  parent  beetle  is  a  handsome 

*  Saperda  Candida  Fab.  Family  Cerambycidoe.  See  E.  P.  Felt,  Bulletin 
74,  N.  Y.  State  Museum,  p.  23,  which  gives  full  bibliography  to  1902,  and 
F.  E.  Brooks,  Farmers'  Bulletin  675,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 


521 


insect  about  three-quarters  inch  long.  The  antennae  and  legs  are 
gray,  the  head  and  under  surface  of  the  body  silvery  white  and 
the  upper  surface  is  light  brown  with  two  longitudinal  white  stripes. 
Life  History. — The  beetles  emerge  from  late  May  to  the  middle 
of  July  and  the  females  soon  commence  to  deposit  their  eggs.  The 
female  eats  out  a  little  slit  in  the  bark,  in  which  the  egg  is  inserted 
and  often  pushed  under  the  bark  and  then  covered  with  a  gummy 
substance.  It  is  a  pale  rust-brown  color,  about  one-third  inch 
long,  of  a  broad  oval  shape,  and  usually  concealed  on  young  trees. 
The  egg  hatches  in  two  or  three  weeks.  The  young  larvae  tunnel 
jiist  under  the   bark  on  the  sap-wood,   usually  working  down 


Fig.  450. — Work  of  the  round-headed  apple-tree  borer:  a,  puncture  in  which 
egg  is  laid;  b,  same  in  section;  e,  hole  from  which  beetle  has  emerged; 
/,  same  in  section;  g,  pupa  in  its  ceil.     (After  Riley. — ) 

toward  the  base  of  the  tree,  the  bark  over  these  burrows  often 
cracking  the  next  spring,  and  the  fine  castings  and  borings  sifting 
out.  At  the  beginning  of  the  second  year  the  larva  is  about 
five-eighths  inch  long.  The  larva  continues  in  the  sap-wood 
during  the  second  season,  and  it  is  at  this  time  the  most  serious 
damage  is  done,  for  where  several  occur  in  a  tree  they  almost 
girdle  it.  The  next  season  they  penetrate  into  the  heart-wood, 
and  several  of  them  will  fairly  riddle  a  small  tree  w^th  their 
cylindrical  burrows.  The  full-gro^\Ti  larva  continues  this  burrow 
out  into  the  bark,  often  cutting  clear  across  a  tree.  The  upper 
part  of  the  burrows  are  stuffed  with  fine  borings  and  the  lower 


522        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


part  with  long  wood  fibres.  The  full-grown  larva  is  a  light 
yellowish,  cylindrical  grub,  about  three-quarters  inch  long.  The 
head  is  small,  legs  are  lacking,  and  the  body  tapers  gradually 
from  the  thorax  backward,  the  segments  being  quite  constricted. 
The  third  spring  the  larvse  transform  to  pupae  and  about  three 
weeks  later  the  adult  beetles  emerge  through  large  round  holes. 
This  habit  is  varied,  according  to  Brooks,  in  some  localities 
the  majority  of  the  beetles  emerge  in  two  years  from  the  time 


Fig.  451. — Young  apple  tree  protected  from  borers  by  a  wire  screen  pro- 
tector.    Photo  by  W.  E.  Rumsey. 

of  hatching  in  place  of  in  three,  as  is  generally  the  case  in  the 
northern  range  of  the  insect. 

Control. — The  females  may  be  prevented  from  laying  their 
eggs  by  wrapping  the  trunks  with  wire  netting,  building  paper, 
or  wood  veneer.  If  non-rusting  wire  netting  is  used  it  may  be 
left  on  and  will  also  protect  the  trees  from  mice  and  rabbits. 
The  paper  or  wood  wrappings  should  be  applied  about  May  1st, 
and  removed  in  late  summer.  They  should  be  tied  to  the  tree 
tightly  just  below  the  .crotch  and  should  extend  an  inch  or  two 
into  the  soil  below.     The  wire  netting  should  be  held  out  from  the 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 


523 


trunk  of  the  tree  by  a  layer  of  cotton 
batting  under  it  at  the  upper  end. 
Various  washes  have  been  used  to 
repel  the  beetles.  Thick  whale-oil 
or  caustic  soft-soap  to  which  a  pint 
of  crude  carbolic  acid  is  added  to 
every  10  gallons  is  often  used  and 
should  be  painted  over  the  trunk  so 
as  to  form  a  thick  coating.  Others 
recommend  a  thick  coating  of  white- 
wash to  which  a  little  Portland 
cement  is  added  to  make  it  more 
adhesive.  These  should  be  applied 
by  the  middle  of  May  and  as  often 
as  need  be  to  keep  the  trunk  covered 
until  late  summer.  Asphaltum, 
melted  and  painted  onto  the  trunks, 
gives  better  results  than  any  of  the 
other  materials  of  this  nature,  accord- 
ing to  results  secured  in  West  Vir- 
ginia, but  none  of  the  treatments 
seems  to  be  entirely  satisfactory. 
If  the  trees  are  gone  over  every 
fall  and  spring,  the  egg  scars  and 
burrows  of  the  young  larvse  may  be 
detected  and  these  may  be  cut  out 
while  still  in  the  sap-wood,  without 
much  injury  to  the  tree.  When  the 
borers  get  into  the  heart-wood  it  is 
almost  impossible  to  dig  them  out 
without  doing  more  injury  to  the  tree, 
but  they  may  sometimes  be  destroyed 
by  injecting  carbon  bisulfide  into  the 
burrows  and  plugging  the  aperture 
with  putty  or  clay.  Where  a  tree 
has  been  nearly  or  quite  girdled,  it 
may  sometimes  be  saved  by  bridge- 
grafting.  Orchards  kept  free  of  grass 
and  weeds  and  trees  with  smooth 
healthy  bark  are  much  less  affected. 
Brooks  reports,  also,  that  the  beetles 


Fig.  452. —  Young  tree  painted 
with  asphaltum  to  keep  out 
borers.  Photo  by  W.  E.  Rumsey. 


524       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


may  be  poisoned  by  arsenicals;  if  so,  the  codling  moth  spray  prob- 
ably is  responsible  for  smaller  numbers  of  borers  being  found  in 
sprayed  orchards  than  in  neglected  ones. 

The  Flat-headed  Apple-tree  Borer  * 

This  species  is  more  abundant  than  the  preceding,  but  does 
less  damage.     It  prefers  trees  which  have  been  weakened  or  are 

diseased,  and  attacks  almost  all 
of  the  common  orchard  trees 
as  well  as  numerous  shade  and 
forest  trees,  so  that  it  is  every- 
where common.     The  species 
is  found  from  southern  Can- 
ada to  Mexico.   The  larvse  live 
just  beneath  the  bark,  where 
they    hollow    out   broad    flat 
Fig.    453.— ThTTat-headed  apple-tree  channels  which  extend  sHghtly 
borer     (Chrysobothris  /emora to  Fab.):  into  the  sap-WOod.    Theinfest- 
a,   larva;   b,   beetle;   c,   head  of  male;     ..  ,        i   .      ,     i  i       .i 

d,  pupa— twice  natural  size.    (After  ation  may  be  detected  by  the 
Chittenden,  U.  S.  Dept.  Agr.)  discoloration   of  the   bark. 

Where  abundant  they  will  often  completely  girdle  young  trees, 
thus  causing  their  death,  and  they  are  frequently  found  abundant 
under  the  loosening  bark  of  the  djdng  limbs  of  large  trees,  as 
they  infest  not  only  the  trunks,  but  the  lower  Hmbs.  The  adult 
beetle  is  about  one-half  inch  long,  dull  metalHc  brown  above,  and  the 
wing-covers  taper  sharply  at  the  tip,  somewhat  Like  a  click  beetle. 
The  wing-covers  are  ornamented  as  shown  in  the  figure,  and 
beneath  them,  as  seen  when  in  flight,  the  body  is  a  bright  metallic 
greenish-blue.  The  male  is  smaller  and  the  head  is  green.  The 
beetles  are  active  during  the  heat  of  the  day  and  may  often  be 
found  on  logs  or  injured  trees. 

Life  History. — The  beetles  emerge  from  the  middle  of  May  until 
mid-summer.  The  eggs  are  deposited  in  crevices  of  the  bark, 
several  often  being  laid  together.  The  eggs  are  yellowish,  irreg- 
ularly ribbed  and  about  one-fiftieth  inch  long.  The  species 
receives  its  name  from  the  shape  of  the  larva,  the  thorax  of  which 
is  very  broadly  expanded,  so  that  it  looks  like  the  head,  which  is 
very  small  and  almost  concealed  by  it.  The  abdomen  is  much 
smaller  and  the  whole  body  is  flattened.     The  larva  is  about 

*  Chrysobothris  femorata  Fab.    Family   Buprestidoe.     See  F.    E.    Brooks, 
Farmers'  Bulletin  1065,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR        525 


one  inch  long,  and  usually  rests  in  the  curved  position  shown  in 
Fig.  453.  The  larva  becomes  full  grown  in  a  single  year  and  in 
the  South  may  pupate  in  November,  but  in  the  North  does  not 
pupate  until  the  next  spring,  when  it  remains  as  a  pupa  about 
three  weeks.  The  beetle  emerges  through  an  elliptical  exit  hole, 
in  contrast  to  the  round  hole  of  the  round-headed  borer. 

Control. — As  this  beetle  is  everywhere  present,  injury  may 
always  be  expected  if  trees  are  not  kept  in  a  healthy  condition, 
but  if  the  orchard  is  well  cared  for  it  seldom  suffers  much  damage. 
The  same  measures  for  preventing  oviposition  as  suggested  for 
the  previous  species  are  advised,  but  the  repellant  washes  must 
be  applied  higher  on  the  trunks  and  should  extend  to  the  lower 
branches  as  high  as  can  be  reached. 

The  Oyster-shell  Scale  * 

Not  infrequently  young  apple  and  pear  trees  are  encrusted  and 
killed  by  the  Oyster-shell  Scale,  as  are  young  poplars  and  maples. 
It  is  probably  our  most  com- 
mon scale  insect,  being  al- 
most always  found  on  apple 
trees,  on  which  it  works  on 
the  bark  or  the  twigs  and 
trunk,  reproducing  even  on 
old  trunks,  where  the  scales 
will  be  found  under  the  loose 
bark  and  are  undoubtedly 
a  factor  in  causing  the  bark 
to  slough  off.  All  of  the 
common  orchard  trees  are 
occasionally  infested  but 
rarely  injured,  as  are  also 
maple,  poplar,  horse-chest- 
nut, willow  and  lilac. 
Quaintance  and  Sasscer  give 
a  Ust  of  over  100  trees, 
shrubs,  and  plants  upon 
which  the  scales  have  been 
found.  The  species  is  a  cos- 
mopobtan  one,  having  been 

*  Lepidosaphes  ulmi  Linn.  Family  Coccidoe.  See  Quaintance  and  Sasscer, 
Farmers'  Bulletin  723,  U  S.  Dept.  Agr.,  and  references  there  given. 


Fig.  454. — The  oyster-shell  scale  {Lepid- 
osaphes ulmi  Linn.):  a,  female  scales  on 
twig;  h,  female  scales  from  above;  c, 
same  from  below  showing  eggs;  d,  male 
scale — enlarged.      (After  Howard.) 


'526        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


introduced  into  this  country  at  an  early  date  and  now  being  found 
in  every  State,  and  occurs  throughout  the  world,  where  the  food- 
plants  exist. 

The  mature  female  scale  is  about  one-eighth  inch  long,  of  a 
dark-brown  color,  sometimes  almost  blackish,  and  shaped  some- 
what like  an  oyster-shell,  as  shown  in  Fig.  454.  The  male  scale 
is  much  smaller,  and  with  but  one  cast  skin  at  the  anterior  end, 
as  shown  in  the  same  figure. 

\Life  History. — If  one  of  the  female  scales  be  turned  over 
during  the  winter,  numerous  oval,  white  eggs  will  be  found  under 
it,   with  the  shriveled  body  of  the  female  insect  tucked  away 


a. 


Fig.  455. — Three  common  scale  insects;  a,  oyster-shell  scale;  h,  scurfy  scale; 
c,  San  Jos6  scale.     All  natural  size.     (Photo  by  Rumsey.) 

at  the  anterior  end.  These  eggs  hatch  a  week  or  two  after  the 
apples  blossom,  producing  small  yellowish  insects,  which  look  like 
mites  as  they  crawl  over  the  bark,  which  they  often  give  a  yel- 
lowish tinge  where  very  abundant.  The  young  insect  is  of 
microscopic  size.  It  settles  down  after  a  few  hours'  wandering 
and  begins  sucking  the  sap  from  the  bark.  In  a  day  or  two 
long,  white  waxy  filaments  exude  from  over  the  body,  which 
soon  mat  down  and  form  the  protecting  scale,  to  which  the  cast 
skins  are  added  when  the  insect  molts.     The  female  loses  her 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR        527 


legs,  antennae,  and  eyes,  after  the  first  molt,  and  when  full  grown 
is  an  elongate,  yellowish,  jelly-like  mass,  being  simply  a  "repro- 
ductive sack,  with  her  sucking  mouth  parts,  through  which  the 
food  is  taken,  inserted  in  the  tissues  of  the  plant."  The  females 
become  full  grown  in  about  eight  to  ten  weeks,  when  they  lay 
from  40  to  100  eggs  and  then  die.  In  the  North  there  is  but 
one  generation  a  year,  but  from  the  District  of  Columbia  south- 
ward there  is  a  partial  or  complete  second  generation.  When 
the  male  insects  are  full  grown  they  emerge  from  the  scales  as 
two- winged  flies,  fertilize  the  females  and  die  at  once. 
Control. — See  below 

The  Scurfy  Scale  * 

"The  Scurfy  Scale,  while  infesting  a  considerable  number  of 
plants  (some  35  in 
number),  is  a  less 
general  feeder  than 
the  preceding  spe- 
cies. It  occurs  prin- 
cipally upon  ros- 
aceous plants,  such 
as  the  apple,  peach, 
pear,  plum,  cherry, 
etc.,  and  also  on 
currant  and  goose- 
berry among  cultiv- 
ated plants,  but 
seldom  becomes  so 
abundant  as  to 
cause  particular  in- 
jury  or  require 
specific  treatment. ' ' 
It  is  especially  com- 
mon on  apple  and 


t 


Fig.  456. — ^The  scurfy  scale   (Chionaspis  furfura 
Fitch) :  a,  c,  females,  b,  d,  males — a,  b,  natural 
size,  c,  d,  enlarged.     (After   Howard,    U.    S. 
Dept.  Agr.) 


pear  and  less  so  on  cherry  and  peach,  though  it  has  been  observed 
as  quite  destructive  to  peach  in  the  South,  greatly  stunting  the 
trees,  though  none  were  actually  killed.     The  female  scale  is  a 


*  Chionaspis    furfura    Fitch.     Family    Coccidw. 
Sasscer,  I.e. 


See    Quaintance    and 


528       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

dirty-gray  color,  irregularly  shaped  as  shown  in  Fig.  456,  c 
The  male  scale  is  much  smaller,  elongate,  snowy  white,  and  with 
three  distinct  ridges,  Fig.  456,  d.  It  is  an  American  insect, 
being  common  from  Southern  Canada  to  the  GuK  States.  The 
life  history,  as  far  as  known,  is  practically  identical  with  that 
of  the  last  specjes. 

Control. — As  the  last  two  species  are  practically  identical  in 
habits,  they  may  be  controlled  by  the  same  methods.  Where 
the  trees  are  sprayed  with  lime-sulfur  wash  for  the  San  Jose  scale, 
there  will  be  but  little  trouble  with  these  scales,  and  where  specific 
treatment  is  required  for  them  experiments  indicate  that  a  thor- 
ough coating  with  the  lime-sulfur  wash  while  the  trees  are  dor- 
mant, preferably  in  the  spring  just  before  the  buds  open,  is  one 
of  the  most  effective  remedies.  The  wash  does  not  seem  to  kill 
the  eggs,  but  to  kill  the  young  soon  after  hatching,  and  has  been 
used  successfully  on  both  fruit  and  shade  trees,  but  if  there  be 
frequent  rains  in  late  spring,  so  that  it  is  washed  off,  or  if  the 
scales  are  very  thick,  it  is  not  always  entirely  effective,  but  yearly 
treatments  will  always  prevent  serious  damage. 

Apple  Plant-lice  * 

Several  species  of  aphids  or  plant-lice  commonly  infest  the 
foliage  of  the  apple,  and  less  commonly  that  of  the  pear,  and 
though  they  differ  somewhat  in  appearance  and  habits  they  are 
sufficiently  alike  to  be  discussed  together,  as  the  same  methods 
of  control  apply  to  aU. 

The  Apple-aphis  f 

This  is  the  common  Apple-aphis  of  Europe,  and  was  first 
noticed  in  this  country  late  in  the  last  century,  when  it  spread 
to  all  parts  of  the  country  within  a  few  years,  probably  being 

*  See  Sanderson,  13th  Report,  Del.  Agr.  Exp.  Sta.;  A.  L.  Quaintance, 
Circular  81,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  Gillette  and  Taylor, 
Bulletin  133,  Colo.  Agr.  Exp.  Sta.,  Parrott,  Hodgkiss  and  Lathrop,  Bulletins 
402,  415  and  431,  N.  Y.  Agr.  Expt.  Station,  Quaintance  and  Baker,  Farmers' 
Bulletin  804,  U.  S.  Dept.  Agr.,  and  Robert  Matheson,  Memoir  24,  Cornell 
Agr.  Expt.  Station. 

t  Aphis  pomi  DeG.  Family  AphididcB.  See  above  references,  and  J.  B. 
Smith,  Bulletin  143,  N.  J.  Agr.  Exp.  Sta.;  C.  P.  Gillette,  Journal  of  Economic 
Entomology,  Vol.  I,  p.  303,  and  H.  E.  Hodgkiss,  Bulletin  461,  N.  Y.  Agr. 
Expt.  Station. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 


529 


distributed  on  nursery  trees.    Only  young  trees  are  usually  much  in- 
jured by  this  and  the  following 


species  of  aphids,  old  trees 
rarely  being  injured,  except 
that  where  the  aphids  are  ex- 
cessively abundant  they 
sometimes  injure  the  young 
fruit,  causing  it  to  become 
stunted  and  misshapen.  The 
f  oUage  of  young  trees  soon  be- 
comes covered  with  the  ver- 
min, which  feed  on  the  under 
surfaces  of  the  leaves,  caus- 
ing them  to  curl  up  and  then 
drop.  This  curling  of  the 
foHage  is  more  commonly 
caused  by  this  species  than 
any  other,  though  the  rosj^ 
apple-aphis  has  a  similar  ef- 
fect. The  aphids  secret  the 
sweet  honey-dew  very  pro- p^^457_g^^g^^  ^^^j^^^ppl^.^pj^^^^^^.^ 
fusely  and  so  attract  large  pomi.  After  Baker,  U.  S.  Dept.  of  Agr. 
numbers  of  ants,  which  feed  upon  it.  The  ants  are  always  found 
associated  with  them,  and  the  presence  of  numerous  ants  on  a  tree 


Fig.  458. — The  apple-aphis,  winged  viviparous  female — greatly  enlarged. 
is  a  good  indication  of  aphids.     The  honey-dew  soon  covers  badly 


530      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARB 

infested  foliage  and  upon  it  there  grows  a  blackish  fungus  which 
gives  the  leaves  a  sooty  appearance,  often  visible  on  the  twigs 
after  they  drop,  and  a  good  indication  of  injury  by  this  species. 
The  full-grown  wingless  females  are  about  one-twelfth  inch  long, 
and  shaped  as  shown  in  Fig.  457.  They  are  of  a  bright  green 
color,  though  occasionally  yellowish,  and  the  tips  gf  the  ant- 
ennae, honey-tubes,  and  tail  are  black.  The  winged  female  is 
shghtly  longer  and  the  wings  expand  about  one-quarter  inch, 
the  head  is  deep  olive  brown;  the  thorax  is  blackish,  and  there 
are  three  black  spots  on  the  lateral  margin  of  the  abdomen, 
but  otherwise  it  is  colorod  like  the  wingless  female. 


Fig.  459. — Nymphs  of  the  apple-aphis,  clustered  on  a  leaf,  showing  developing 

wing-pads. 

Life  History. — The  minute,  oval,  shining  black  eggs  are  to 
be  found  on  the  twigs  during  the  winter,  especially  at  the 
crotches  and  around  buds  and  scars.  They  hatch  just  before 
the  leaf  buds  open  and  the  young  aphids  become  full  grown  in 
two  or  three  weeks,  all  of  them  being  wingless.  During  the  next 
two  or  three  weeks  each  of  these  females  will  give  birth  to  from 
50  to  100  young,  a  few  of  which  develop  wings.  All  of  the  aphids 
of  this  second  generation  are  also  females,  which  give  birth  to 
live  young  without  the  intervention  of  males,  which  do  not  appear 
until  fall.  Their  young  develop  in  a  week  or  ten  days  and  most 
of  them  become  winged  and  migrate  to  other  trees.  The  develop- 
ment and  reproduction  continues  in  this  fashion  throughout  the 
summer,  both  winged  and  wingless  females  being  found  in  most 
colonies,   though  the  size  and   coloration  differ  in  the  various 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 


531 


generations.  Those  which  are  to  become  winged  may  be  dis- 
tinguished after  the  third  molt  by  the  blackish  wing-pads  at 
the  sides  of  the  body.  With  the  first  frost  of  fall  the  young 
develop  into  true  males  and  females.  Both  are  wingless,  the 
male  being  much  the  smaller,  has  long  antennae,  is  yellowish  or 
rusty-brown,  and  is  very  active,  while  the  female  is  larger,  moves 
more  slowly  and  is  lighter  in  color,  but  later  becomes  a  very 


■     "W/""- 

fll 

*\hAA4 

§_ 

\^M^^^^^ 

^^^^^^^^^^^ 

%^^^py/r^ 

rv 

\i^^ 

1^ 

^-\L^     ■ 

f^ 

if                                                  .L^      ^H 

.  J, 

Fig.  460.— The  apple-aphis;  a,  young  tree  partially  defoliated  by  the  aphis; 
d,  winter  eggs  on  twig. 

dark  green.  The  sexes  mate  and  the  females  lay  1  to  3  eggs  in 
the  places  mentioned.  All  of  .the  aphids  die  by  late  fall  and 
the  eggs  remain  to  give  rise  to  new  colonies  in  the  spring. 

With  the  rapid  multiplication  above  described  it  is  not  surpris- 
ing that  the  foliage  is  soon  covered  with  thousands  of  aphids, 
and  that  with  so  many  sucking  the  sap  the  leaves  soon  curl  up 
and  drop.  This  is  often  a  serious  drain  upon  the  vitality  of  young 
trees,  stunting  their  growth,  and  so  weakening  them  that  they 


532       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

are  more  liable  to  be  attacked  by  other  insects  and  diseases, 
while  the  premature  dropping  of  the  foliage  prevents  the  full 
growth  of  the  tree  and  the  proper  hardening  of  the  wood  before 
winter.  This  species  shows  marked  preference  for  certain  varieties 
of  apples  and  rarely  injures  others.  Apple,  pear  and  quince  are 
the  only  fruit  trees  infested  by  this  species,  which  lives  upon 
them  throughout  the  year. 

These  lice  may  also  attack  the  fruit  as  it  begins  to  set,  causing 
some  dropping  and  a  considerable  amount  of  distortion  to  the 


Fig.  461. — ^The  apple-aphis,  winged  fall  migrants  on  leaf — natural  size. 

fruit.  Such  fruits  rarely  attain  full  size  and  may  easily  be  recog- 
nized at  picking  time.  The  rosy-aphis  causes  somewhat  similar 
injury  which  may  be  even  more  severe.  In  normal  years  the 
injury  to  the  fruit  amounts  to  as  much  as  the  injury  to  the  fohage. 

The  Rosy  Apple-aphis  * 

This  species  is  larger  than  the  preceding,  with  a  rounder  body, 

and  is  commonly  of  a  rosy  color,  though  the  wingless  females 

vary  from  a  salmon  or  tan  color  to  slaty  gray,  purplish  or  black. 

It  has  been  injurious  only  to  apple  iii  this  country,  where  it  has 

become  widely  distributed,  but  in  Europe  its  native  food-plants 

are  various  wild  species  of  Sorhus   and  Crataegus.     The  wingless 

female  is  about  one-tenth  inch  long,  the  head,  thorax  and  margin 

*  Aphis  sorbi Kaltenbach.  Family  Aphididcp.  See  Sanderson,  and  Gillette 
and  Taylor  (Aphis  pyri  Boyer),  cited  above;  and  W.  E.  Britton,  9th  Report, 
State  Entomologist  of  Connecticut,  p.  343,  also  other  citations  below  "Apple 
Plant-lice,"  and  A.  C.  Baker  and  W.  F.  Turners,  Jour.  Agr.  Research,  Vol. 
VII,  No.  7. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 


533 


of  the  abdomen  being  dark  reddish-brown,  and  covered  with  a 
powdery  substance  which  gives  it  a  deep  blue  color,  the  middle 
of  the  abdomen  being  lighter  yellowish.  The  antennae  and  legs 
are  whitish,  marked  with  dusky.  The  honey-tubes  are  pale  yellow, 
tipped  with  black,  and  are  long  and  tapering.  Between  the  eyes 
are  two  small  tubercles,  and  on  the  middle  of  the  two  segments 
in  front  of  the  tail  are  a  pair  of  similar  small  tubercles,  which 
are  quite  characteristic  of  this  species.  When  fully  developed 
the  female  becomes  much  darker  and  distended  with  young,  which 
may  be  seen  through  the  abdomen.     The  winged  female  is  about 


Fig.   462. — The   rosy   apple-aphis    (Aphis  sorbi   Kalt.):   winged   viviparous 
female  greatly  enlarged. 

the  same  length,  the  head,  thorax  and  honey-tubes  being  black, 
and  the  abdomen  yellowish-red.  The  winged  females  in  the  fall 
differ  from  those  of  the  spring  in  lacking  the  small  tubercles 
between  the  eyes,  but  both  spring  and  fall  winged  females  have 
the  two  pairs  of  small  tubercles  in  front  of  the  tail.  They  also 
differ  in  having  a  large  black  splotch  on  the  centre  of  the  abdomen, 
bands  across  the  terminal  abdominal  segments,  and  spots  along 
the  sides,  also  black.  The  male  is  winged  and  similar  to  the  winged 
viviparous  females  which  migrate  back  to  the  apple  in  fall. 
The  egg-laying  females  are  wingless,  very  much  smaller  than 
the  summer  forms,  and  light  lemon-yellow  in  color. 


534      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Life  History  — 
the   last   species, 


The  eggs  occur  on  the  twigs,  as  do  those  of 
hatch  about  the  same  time,  and  the  first 
two  or  three  generations  de- 
velop on  the  apple  in  the 
same  manner.  Like  the  last 
species,  the  third  generation  is 
mostly  winged  females  which 
migrate  from  the  apple  to  some 
unknown  food-plant,  on  which 
they  pass  the  summer.  The 
winged  females  return  to  the 
apple  f oUage  in  thefall  and  then 
give  birth  to  young,  which  de- 
velop into  the  true  males  and 
females,  which  may  be  found 
Fig.  463.-The  rosy  apple-aphis,  wingless  laying  their  eggs  in  company 
viviparious  female— greatly  enlarged.     y^]^\^  ^^g  l^st  and  other  species. 

This  species  curls  the  leaves  to  a  greater  extent  than  does  the 
apple  aphis,  and  is  likewise  accompanied  by  ants.  Dr.  Britton 
states  that  "the  rosy  apple  aphis  .  .  .  seems  especially  prone 
to  attack  the  fruit  spurs  and  inner  portions  of  the  tree-top  rather 


Fig.  464. — Apples  showing  typical  aphis  injury.  {Aphis  sorbi.) 
than  the  terminal  twigs  and  exterior  part,"  and  that  it  "affects 
seriously  the  growth  of  the  fruit,"  preventing  its  growth  and  de- 
velopment, and  causing  it  to  be  gnarled  and  irregular  in  shape, 
similar  to  the  damage  by  the  last  species  sometimes  observed. 
(See  accompanying  figure). 


INSECTS  INJURIOUS  TO  THE  A.PPLE  AND  PEAR  535 

The  European  Grain-aphis  * 

This  species  is  found  on  the  apple,  pear,  quince  and  plum  in  the 
spring  and  fall  and  on  the  small  grains  and  various  grasses  during 
the  summer.  Until  recently  it  has  been  the  more  common  form 
on  apple  in  the  East,  but  is  not  now  so  numerous  as  the  apple- 
aphis.  It  is  an  old  European  species  and  was  evidently  imported 
to  this  country  at  an  early  date,  as  it  is  widely  distributed  through 
out  the  United  States.  The  wingless  females  are  distinctly 
smaller  than  the  previous  species,  and  are  of  a  light  green  color, 
marked  with  transverse  diamond-shaped  bands  of  darker  green, 


Fig.  465. — The  European  grain-aphis  {Aphis  avencp  Fab.):  wingless  viviparous 
female,  and  egg-laying  or  oviparous  female — greatly  enlarged. 

across  the  abdominal  segments.     The  honey-tubes  are  shorter, 

distinctly  enlarged  at  the  middle  and  flared  at  the  tip,  which 

*Aphis  avence  Fab.  Family  Aphididoe.  See  Th.  Pergande,  Bulletin  44, 
n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr.,  p.  5  and  authors  cited  above.  The  author 
described  this  species  as  Aphis  fitchii  in  1902,  and  although  there  seems  to 
be  no  question  that  it  feeds  on  grains  and  grasses  during  the  summer,  there 
are  several  reasons  for  believing  that  there  are  either  two  species  or  that  the 
life  history  has  not  been  sufficiently  observed.  Thus  in  some  sections  it  is 
exceedingly  common  on  grain  but  rare  on  apple,  and  in  others  just  the  opposite 
condition  is  found.  Matheson,  I.e.,  uses  for  this  insect  the  name  Aphis  avence 
Fab.,  but  Baker  and  Turner,  Journal  Agr.  Research,  Vol.  XVIII,  No.  6,  call 
the  species  on  apple  the  apple-grain  aphis  and  ascribe  to  it  the  name  Rho- 
palosiphum  pnmifoliae  Fitch.  They  maintain  that  the  name  Aphis  avence  is 
a  synonym  for  R.  padi  L.  It  is  to  be  hoped  that  the  systematists  in  this 
group  will  soon  come  to  an  agreement  for  the  sake  of  uniformity.  It  should 
be  mentioned  that  the  latter  authorities,  I.e.,  under  Rosy  Apple-aphis,  considei 
that  species  as  Aphis  malijolice  Fitch  rather  than  as  A.  sorbi  Kaltenbach. 


536       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


distinguish  the  species  of  this  genus.  The  winged  female  has 
the  head  and  thorax  blackish,  and  the  abdomen  yellowish-green 
or  brownish,  usually  lacking  the  greenish  bands  of  the  wingless 
form,  and  the  honey-tubes  are  brown  with  rusty  spots  around  the 
base.  The  species  may  be  distinguished  by  the  very  short  second 
fork  of  the  median  vein  at  the  tip  of  the  fore- wings. 

Life  History. — The  eggs  are  found  on  the  apple  and  pear,  and 
the  first  two  generations  in  the  spring  develop  as  do  those  of  the 
preceding  species.  All  of  the  second,  or  sometimes  the  third, 
generation    become    winged   and    migrate   to   small   grains   and 


Fig.  466. — The  European  grain-apliis,  migrating  winged  viviparous  female 
of  the  second  generation — greatly  enlarged. 

grasses,  on  which  they  feed  during  the  summer.  In  the  fall 
winged  females  return  to  the  fruit  trees  and  give  birth  to  young, 
which  develop  into  wingless  females  and  winged  males,  which  mate 
and  produce  the  winter  eggs.  Pergande  states  that  "  the  species 
is  biennial  and  that  the  progeny  of  the  spring  migrants  from  the 
apple  subsist  almost  exclusively  upon  various  grains  and  grasses 
until  the  fall  of  the  second  year,  when  a  generation  of  return 
migrants  makes  its  appearance."  This  is  certainly  true  in  the 
South,  where  the  aphids  may  be  observed  on  grains  throughout 
the  winter,  but  it  may  be  questioned  whether  they  usually  survive 
the  winter  on  grains  or  grasses  in  the  North. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR         537 

Professor  F.  M.  Webster*  has  observed  this  species  on  wheat  in 
Ohio,  and  states  that  in  mild  winters  it  remains  on  the  wheat, 
going  down  on  the  stems  to  just  below  the  surface  of  the  soil  or 
to  the  upper  roots,  as  we  have  observed  it  in  Texas.  ''Here  they 
go  on  reproducing  when  the  temperature  is  favorable,"  he  says, 
"the  adults  being  apterous  so  far  as  observed  by  me,  until  spring, 
when  they  ascend  to  the  foliage,  the  adults  after  this  being  both 
winged  and  wingless.  On  the  stems  and  roots  below  the  surface 
of  the  ground  they  are  of  a  greenish  color,  tinged  with  reddish- 
brown,  especially  posteriorly,  the  full-grown  individuals  often 
being  wholly  of  a  dark  brown.  It  is  during  autumn  that  they 
do  their  greatest  injury  to  the  wheat  by  sucking  the  juices  from 
the  young  plants,  often,  if  on  poor  land  and  if  in  dry  weather, 
checking  their  growth  and  causing  the  foliage  to  turn  yellow." 
This  species  is  seldom  much  in  evidence  on  grains  or  grasses  in 
midsummer  and  rarely  becomes  very  injurious  to  them.  On 
the  apple  it  is  abundant  on  the  young  fohage  and  particularly  on 
the  flower  buds  and  blossoms,  where  it  is  much  more  common  than 
the  other  species.  It  does  not,  however,  curl  the  foliage  nearly 
as  severely  as  the  other  species,  due  to  its  earHer  migration. 
■-  Control. — It  has  been  found  in  many  places  that  by  delaying 
the  lime-suKur  spray  as  appHed  for  scale  until  the  buds  are 
beginning  to  open  in  the  spring  the  grower  may  effectively  con- 
trol the  aphis,  the  spray  killing  at  this  time  the  over-wintering 
eggs.  It  must  be  admitted,  however,  that  there  are  times  when 
this  treatment  is  not  effective.  Just  why  is  not  known.  When 
this  spray  is  omitted  or  fails  to  kill  the  aphids,  they  may  be 
controlled  by  spraying  with  Blackleaf  40  at  the  rate  of  1  to  1000, 
four  pounds  of  soap  being  added  to  the  mixture  if  it  is  applied 
without  bordeaux  or  the  arsenicals.  Hodgkiss  recommends  a 
spray  called  the  nicotine-lime  spray,  made  by  adding  two  to 
four  pounds  copper  sulphate  and  six  pounds  lime  to  the  1  to 
1000  solution  of  nicotine  sulphate  (Blackleaf  40).  The  above 
amount  for  each  100  gallons  of  the  spray.  This  acts  to  some 
extent  as  a  deterrent  as  well  as  an  insecticide.  Any  spraying 
done  must  be  done  before  the  leaves  curl,  since  the  insects  must 
be  hit  with  the  spray  to  be  killed  and  when  they  are  protected 
by  curled  leaves  it  is  impossible  to  hit  any  great  number  of  them. 
*See  Bulletin  51,  Ohio  Agr.  Expt.  Station,  p.  111. 


538        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Tent  Caterpillar  * 

From  the  earliest  times  the  webs  of  the  tent  caterpillar  have 
adorned  the  neglected,  wayside  apple  and  cherry  trees  in  all 
parts  of  the  country  east  of  the  Rocky  Mountains.  On  the 
Pacific  coast  a  nearly  related  species  has  very  similar  habits. 
The  adult  moths  are  common  in  July  in  the  North  or  in  May  in 
the  Gulf  States.  They  are  stout-bodied,  of  a  reddish-brown 
color,  with  two  nearly  parallel  white  bands  extending  obhquely 
across  the  fore-wings.  The  females  have  a  wing  expanse  of  about 
1|  inches,  while  the  males  are  smaller  and  may  be  distinguished 
by  their  feathery  antennae.  The  sexes  soon  mate  and  the  females 
deposit  their  eggs  about  five  or  six  weeks  after  apples  blossom. 
The  egg-mass  is  from  one-half  to  three-quarters  inch  long  and 
forms  a  grayish-brown,  knot-like  band  around  the  twig  on  which 
it  is  laid,  closely  resembUng  the  bark  in  color.  Each  mass  con- 
tains about  200  eggs,  placed  on  end,  packed  closely  together  and 
covered  with  a  light  brown,  frothy  glue,  which  gives  a  tough, 
smooth,  ghstening  surface  to  the  whole  mass.  The  little  cater- 
pillars hatch  just  as  the  leaf  buds  are  expanding  in  the  spring. 
Ofttimes  they  emerge  before  the  leaf-buds  have  expanded  suf- 
ficiently to  furnish  any  food,  in  which  case  they  satisfy  their 
hunger  with  the  glutinous  covering  of  the  egg-mass,  spinning  a 
thin  web  over  it.  Soon  they  are  able  to  bore  into  the  buds  and 
a  web  is  commenced  at  the  nearest  crotch.  Wild  cherry  and 
apple  are  the  favorite  food-plants  and  are  often  stripped  of  their 
foliage  year  after  year,  but  all  of  the  common  fruit  trees  are  more 
or  less  frequented,  and  when  very  abundant  the  common  shade 
trees  are  attacked  and  occasionally  one  is  defoliated.  The  little 
caterpillars  from  one  egg-mass  cooperate  in  spinning  the  tent 
which  furnishes  them  shelter  at  night  and  during  cold  or  wet 
weather.  This  is  gradually  enlarged  with  new  layers  of  silk, 
the  caterpillars  living  beneath  the  outer  layers.  The  caterpil- 
lars are  grown  in  five  or  six  weeks,  when  they  become  exceed- 
ingly restless  and  wander  away  from  the  nest  in  search  of  suit- 
able places  for  spinning  their  cocoons.  The  full-grown  caterpil- 
lar is  about  two  inches  long,  deep  black  in  color,  sparsely  covered 
with  yellowish  hairs,  with  a  white    stripe    down    the   middle  of 

*  Malacasoma  americana  Fab.  Family  Lasiocompidce.  See  A.  L.  Quaint- 
ance,  Farmers'  Bulletin  662,  U.  S.  Dept.  Agr.;  V.  H.  Lowe,  Bulletin  152, 
N   Y  Agr.  Exp.  Sta.;  E.  P.  Felt,  14tli  Report  State  Ent.  N.  Y.,  pp.  177-190. 


INSECTS  mjURIOUS  TO  THE  APPLE  AND  PEAR  539 


Fig.   467.  —  Egg    mass  on 
twig — natural  size. 


Fig.  468. — Egg  mass  cov- 
ered with  web  of  newly 
hatched  ca,terpillars. 


Fig.  4ljy. — Aesvly-formed  web. 


Fig.   4(0.  —  Web    bearing    half-grown 
caterpillars — reduced  in  size. 


540         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


the  back.     On  the  side  of  each  segment  is   an   oval  pale  blue 

spot  with  a  broader  vel- 
vety black  spot  adjoin- 
ing it  in  front,  giving 
somewhat  the  effect  of  an 
eye-spot.  Having  found  a 
suitable  place  under  loose 
bark,  in  a  fence,  in  the 
grass  or  rubbish  beneath 
the  tree,  or  in  the  shelter 
of  some  neighboring  build- 
ing, the  caterpillar  settles 
down  and  proceeds  to  en- 
case itself  in  a  thin  cocoon 
of  tough  white  silk,  in  which 
it  transforms  to  the  pupa. 
About  three  weeks  later 
the  adult  moth  emerges 
from  the  pupa  to  con- 
tinue the  life  cycle,  there 

Fig.   471.— Tent  caterpillars  on  web— one-  being    but  one  generation 
half  natural  size.     (Photo  by  Weed.) 

a  year. 

The   caterpillars  are  held  in   check   by   numerous   parasitic 


Fig.  472. — ^The  tent  caterpillar  moth.     (After  Lowe.) 
insects,  some  24  species  having  been  found  preying  upon  them 
by  Mr.  W.  F.  Fiske  in  New  Hampshire,*  as  well  as  by  preda- 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 


541 


ceous  soldier  bugs  (Podisus  spp.)  and  many  of  our  common  birds. 
Large  numbers  of  the  caterpillars  are  also  carried  off  by  a  bac- 
terial disease. 

Several  species  of  little  chalcis-flies  are  parasitic  in  the  eggs 
and  destroy  a  large  proportion  of  them.  Were  it  not  for  these 
natural  enemies  the  tent  caterpillar  would  become  a  much  more 
serious  pest. 

Control. — The  egg-masses  may  easily  be  detected  and  pruned 
off  during  the  winter,  and  it  would  be  well  to  leave  them  in  a  box 


Fig.  473. — Cocoons  of  the  tent  caterpil- 
lar, natural  size.      (After  Lowe.) 


Fig.  474. — Web  of  the  tent  cater- 
pillar riddled  by  birds.  (Photo 
by  Weed.) 


covered  with  netting  so  that  the  parasites  may  escape.  Neglected 
apple  and  wild-cherry  trees  should  be  destroyed,  as  they  harbor 
this  and  other  pests  and  are  usually  valueless.  The  caterpillars 
may  be  quickly  destroyed  by  spraying  with  Paris  green  or  arse- 
nate of  lead  just  after  the  foliage  comes  out,  before  the  trees 
blossom.     If  there  are  but  a  few  nests  the  caterpillars  may  be 

*  See  W.  F.  Fiske,  Tech.  Bulletin  6,  N.  H.  Agr.  Exp.  Sta. 


542      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


destroyed  in  them  by  spraying  the  nest  on  a  cloudy  or  cool  day 
with  pure  kerosene.  Apply  the  spray  with  an  extension  rod  and 
fine  nozzle  so  that  the  nest  will  be  thoroughly  soaked,  without 
spraying  the  surrounding  foliage.  Or  the  caterpillars  may  be 
destroyed  by  burning  the  nests  with  a  torch  while  they  are  in 
them,  or  while  young  they  may  be  swabbed  out  with  a  broom  or 
brush  and  crushed. 

No  injury  need  be  feared  in  an  orchard  sprayed  for  codling- 
moth  and  other  insects. 

The  Yellow-necked  Apple  Caterpillar  * 

During  late  summer  the  tips  of  apple  limbs  are  often  found 
defoHated  for  a  foot  or  two  and  if  examined  a  mass  of  caterpillars 

will  be  found  huddled  together 
as  if  confessedly  guilty.  Us- 
ually these  will  prove  to  be- 
long to  this  or  the  following 
species.  The  full-grown  yel- 
low-necked apple  caterpillar 
is  about  two  inches  long,  with 
a  jet  black  head  and  the  next 
segment,  often  called  the  neck, 
a  bright  orange-yellow,  from 
which  the  insect  is  named. 
Down  the  middle  of  the  back 
runs  a  black  stripe,  and  on 
either  side  of  the  body  are 
three  stripes  of  black  alternat- 
ing with  four  of  yellow  and  the 
body  is  thinly  clothed  with 
long,  soft  white  hairs.  While 
young  the   caterpillars  feed 

only  on  the  under  surfaces 
Fig.  475.— Yellow-necked  apple  cater-       .  ,,      ip„„„^    u,-x         .i^       i^ 
pillars  assembled  on  twig  in  natural    ^t  tUe  leaves,  Out  as  tney  De- 
position— from  life,  much  reduced,      come  larger  the  whole  leaf  ex- 
cept the  stem,  is  devoured.     They  feed  together  in  colonies,  usually 
starting  at  the  tip  of  a  limb,  where  the  eggs  were  laid,  and  strip- 

*Datana  ministra  Drury.  Family  Notodontidce.  See  A.  S.  Packard, 
Memoirs  National  Academy  of  Sciences,  Vol.  VII,  p.  106; E.  D.  Sanderson, 
Bulletin  139,  N.  H.  Agr.  Exp.  Sta.,  p.  213. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR  543 

ping  the  foliage  toward  the  base,  and  are  often  found  clustered 
together  in  a  solid  mass.  If  the  limb  is  jarred  or  a  caterpillar 
touched,  it  at  once  assumes  a  position  characteristic  of  this 
genus,  throwing  the  head  and  tail  in  the  air  with  a  jerk  and 
clinging  to  the  hmb  by  the  abdominal  prolegs,  as  shown  in 
Fig.  475.  The  wings  of  the  adult  moth  expand  about  two 
inches  and  are  a  reddish-brown  color,  while  the  head  and 
thorax  are  chestnut-brown.  The  fore-wings  have  three  to 
five  transverse  lines,  one  or 
two  spots,  and  the  outer 
margin  of  a  dark  color,  and 
the  hind-wings  are  pale  yel- 
lowish without  markings. 

Life  History. — The  winter 
is  passed  in  the  pupal  stage 
in  the  soil,  from  which  the 
moths  emerge  from  May  to 
July.  The  round,  white  eggs 
are  laid  on  the  leaves  in 
masses  of  75  to  100,  and  hatch 
during  mid-summer.  The 
caterpillars  feed  during  the 
late  summer  and  become  full 
grown  in  four  or  five  weeks, 

when    they    enter   the   earth    '       ~Z,     ZZ        Z  T"]         i~ 

•^  .  iiG.    4/6. — ine    yellow-necked    apple 

for   from   2    to    4    inches    and       caterpillar   {Datana  ministra  Dru.): 
there     transform     to     naked       mature  larvai  and  moth-natural  size. 

brown  pupae,  without  making  any  cocoons.  There  is  but  one  gen- 
eration in  the  Northern  and  Middle  States. 

The  species  occurs  throughout  the  Northern  and  Middle  States 
east  of  the  Rocky  Mountains,  and  in  the  far  South  there  seem  to 
be  no  records  of  the  species.  Though  most  common  on  apple,  it 
also  feeds  on  pear,  cherry,  quince,  and  plum,  and  on  hickory, 
oak,  walnut,  chestnut  and  other  shade  and  forest  trees,  some- 
times defoliating  them,  as  do  other  nearly  related  species. 

Control. — As  the  work  of  these  caterpillars  is  soon  noticed, 
and  as  they  habitually  feed  in  colonies,  it  is  an  easy  matter  to 
hand  pick  and  destroy  them,  or  swab  them  off  the  limbs  with  a 
rag  or  waste  saturated  with  kerosene,  or  where  a  colony  is  clus- 


544        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

tered  at  the  tip  of  a  limb,  it  may  be  cut  off  and  crushed.  If  this 
and  other  caterpillars  are  abundant  on  the  foliage  in  late  sum- 
mer, it  will  be  well  to  spray  with  arsenate  of  lead,  3  pounds  to 
the  barrel,  while  the  caterpillars  are  small,  which  will  be  about 
six  to  eight  weeks  after  the  apple  blossoms  fall 


The  Red-humped  Apple  Caterpillar  * 

This  species  is  often  associated  with  the  preceding  in  very 
similar  injury,  and  has  practically  the  same  habits.     The  name 

is  given  on  account  of  the  prom- 
inent hump  on  the  fourth  seg- 
ment of  the  larva  which,  with 
the  head,  is  a  bright  coral  red. 
The  mature  caterpillar  is  striped 
with  yellowish-white,  alternating 
with  dark  brown  or  blackish 
lines,  and  a  double  row  of 
black  spines  extends  along  the 
back.  The  fore-wings  of  the 
moth  expand  about  1|  inches, 
are  dark  brown  on  the  inner 
and  grayish  on  the  outer  margin ; 
they  have  a  dark-brown  dot 
near  the  middle,  a  spot  near 
each  angle,  and  several  longi- 
tudinal streaks  of  the  same  color 
along  the  posterior  margin.  The 
hind-wings  of  the  male  are  brown- 
ish and  of  the  female  dusky  brown,  the  body  is  light  brown  with 
the  thorax  of  a  darker  shade. 

This  species  occurs  throughout  the  United  States  and  feeds 
on  apple,  plum,  rose,  thorn,  cherry,  blackberry,  willow,  oak, 
hickory,  and  other  trees  and  shrubs.  The  caterpillars  become 
full  grown  in  late  summer  or  early  fall  and  then  spin  loose  silken 
cocoons  to  which  are  attached  bits  of  earth  and  rubbish,  so  that 

*  Schizura  concinna  Smith  and  Abbott.  Family  Notodontidce.  See  A.  S. 
Packard,  Memoirs  National  Academy  of  Sciences,  Vol.  VII,  p.  212;  E.  D. 
Sanderson,  Bulletin  139,  N.  H.  Agr.  Exp.  Sta.,  p.  216. 


-The  red-humped  apple 


Fig.  477.- 

caterpillar     (Schizura    concinna 
•  S.  &  A.) — slightly  enlarged. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR         545 


they  closely  resemble  their  surroundings  as  they  lie  on  the  ground 
beneath  rubbish,  or  just  under  the  surface  of  the  soil.  After  some 
time  the  larvae  transform  to  pupae,  in  which  stage  the  winter  is 
passed.  Otherwise  the  life  history  is  practically  the  same  as  the 
preceding  species,  except 
that  there  is  some  evidence 
of  there  being  two  genera- 
tions in  the  South.  The 
larvae  of  this  species  are 
very  frequently  parasitized 
by  Uttle  ichneumon-flies  * 
which  destroy  whole  colonies 
of  them  while  still  young,  the 
inflated  skins  being  found  on 
the  under  side  of  a  leaf,  often 
perforated  by  the  round  exit 
holes  of  the  parasite. 

Control. — Same  as  for  the 
preceding  species. 


Fig. 


478. — Eggs    of    the    red-humped 
apple  caterpillar — enlarged. 


The  Apple  Leaf -miner  f 

This  is  the  most  common  leaf-miner  of  the  apple  and  makes 
small  brown  trumpet-shaped  blotches  under  the  upper  surfaces 
of  the  leaves.  It  has  not  been  regarded  as  a  serious  pest  until 
recently,  but  during  the  last  few  years  it  has  become  so  abundant 
as  to  do  serious  injury  to  apple  foliage  in  New  England  and  the 
Middle  Atlantic  States,  in  some  instances  largely  defoliating  the 
trees.  It  is  a  native  insect  which  is  generally  distributed  east  of 
the  Rocky  Mountains 

The  adult  is  a  httle  moth  whose  wings  expand  about  one-third 
inch  and  are  broadly  fringed  as  shown  in  the  figure.  Clemens 
describes  it  as  follows:  "Head  and  antennae  shining  dark  brown, 
face  ochreous.  Fore-wings  uniform,  shining  dark  brown  with  a 
purphsh  tinge,  slightly  dusted  with  pale  ochi'eoue;  ciha  of  the 

*Limneria  fugitiva  Say,  and  L.  oedemasice  Ashm.     Famil  y  I chneumonidoe 

t  Tischeria  malifoliella  Clemens.     Family  Tineidoe.     See  A.  L.  Quaintance, 

Bulletin  68,  Part  III,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  C.  D.  Jarvis, 

Bulletin  45,  Storrs  (Conn.)  Agr.  Exp.  Sta.;  C.  O.  Houghton,  Bulletin  87, 

Del.  Agr.  Exp.  Sta. 


546         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

general  hue.  Hind-wings  dark  gray;  cilia  with  a  rufous  tinge." 
The  full-grown  larva  is  one-third  inch  long,  somewhat  flattened, 
and  tapers  from  the  broad  thorax  to  the  last  segment,  It  is 
light  green  except  the  back  of  the  prothorax  and  the  anal  seg- 
ment, which  are  brown. 

Life  History. — The  moths  emerge  in  late  April  in  Delaware  and 
in  May  in  Connecticut.     The  small  greenish-yellow,  blister-hke 

eggs  are  elliptical  in  outline,  about  one- 
fiftieth  inch  long,  and  are  attached 
closely  to  the  surface  of  the  leaf.  They 
hatch  in  from  eight  to  t  e  n  days  and 
the  young  larvae  mine  directly  into  the 
leaf  from  the  under  side  of  the  eggs. 
The  larvae  become  full  grown  in  about 
three  weeks  and  pupate  in  their  mines, 
the  pupal  stage  lasting  eight  to  ten 
days.  Thus  the  whole  life  cycle  re- 
quires but  about  thirty-three  days  in 
the  District  of  Columbia,  where  there 
are  four  generations  a  year,  and  about 
six  weeks  in  Connecticut,  where  there 
are  but  two  generations.  The  larvae 
of  the  last  generation  Hne  their  mines 
with  silk  and  in  them  pass  the  winter 
in  the  fallen  leaves,  transforming  to 
pupae  the  next  spring. 

Control. — As  the  larvae  pass  the  win- 
ter in  the  fallen  leaves,  the  insect  may 
be    entirely   controlled    by    plowing 
under  the  leaves  in  late  fall  or  early 
spring  or  by  raking  them  up  and  burn- 
FiQ.    479.  — Trumpet -shaped  ing  them.    When  the  larvffi  become  so 
mine  of  the  apple  leaf-miner  abundant  as  to  threaten  serious  injury 
(Tischeria  malijoliella  Clem.)    .  i_      i  -n   j    • 

(Photo  by  Quaintance,  U.  S.  m  summer  they  may  be  killed  m 
Dept.  Agr.)  ^j^gjp  mines  by   spraying   the  foHage 

with  10  to  15  per  cent  kerosene  emulsion,  but  this  is  not  satis- 
factory in  the  early  fall. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 


547 


The  Pistol  Case-bearer*  and  the  Cigar  Case-bearer  f 

These  interesting  little  case-bearers  have  long  been  known  as 
apple  insects,  but  only  in  comparatively  recent  years  have  they 
done  sufficient  injury  to  attract  attention.     Both  species  have 


Fig.  480  — The  pistol  case-bearer  (Coleophora  malivorella  Riley) .  a,  apple 
twig  showing  larval  cases  and  work  on  leaves;  b,  larva;  c,  pupa;  d,  moth, 
6,  c,  d,  enlarged.     (After  Riley.) 

done  serious  damage  in  New  York  by  boring  into  the  young  buds 
and  blossoms,  and  eating  off  the  surface  of  the  leaves,  so  that  in 
some  cases  orchards  have  been  practically  defoliated      The  pistol 


Fig.  481. — ^The  cigar  case-bearer  {Coleophora  flefcherella  Fernald):  a,  adult 
female;  b,  side  view  of  pupa  and  upper  view  of  cremaster  of  same;  c,  larva; 
d,  egg;  e,  venation  of  wings — much  enlarged.  (After  Hammar,  U.  S. 
Dept.  Agr.) 

*  Coleophora  malivorella  Riley.  Family  Elachistidce.  See  V.  H.  Lowe. 
BuUetin  122,  N.  Y.  Agr.  Exp.  Sta. 

t  Coleophora  fletcherella  Fernald.  F&imly  Elachistidce.  See  M.  V.  Slinger- 
land,  Bulletin  93,  Cornell  Univ.  Agr.  Sta. ;  A.  G  Hammar,  Bulletm  80,  Part  II, 
Bmeau  of  Entomology,  U  S.  Dept.  Agr. 


548      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

case-bearer  seems  to  be  generally  distributed  over  the  eastern 
United  States  and  southern  Canada,  while  the  cigar  case-bearer 
is  known  to  occur  in  Canada  from  Nova  Scotia  to  British  Columbia, 
in  New  York,  Michigan,  Kansas  and  New  Mexico.  As  both 
insects  are  readily  carried  on  nursery  stock  they  are  doubtless 
much  more  widely  distributed  than  the  records  indicate. 

Life  History. — The  life  histories  of  the  species  are  very  similar 
and  have  been  most  interestingly  described  in  detail  by  the 
authors  cited.  The  young  caterpillars  hibernate  in  their  little 
cases,  which  are  attached  to  the  twigs  usually  near  or  upon  the  buds. 
Those  of  the  pistol  case-bearer  are  about  one-eighth  inch  long 
and  resemble  the  bark  in  color.  A  short  time  before  the  leaf- 
buds  burst  in  the  spring,  the  larvae  become  active  and  attack 
the  growing  buds,  gnawing  through  the  outer  cover  to  feed  on 

the  tender  tissues  beneath. 
Later  they  feed  on  the  young 
leaves,  making  small  holes 
through  the  surface  and  feed- 
ing on  the  soft  tissue  within  in 
much  the  same  manner  as  a  true 
leaf-miner  In  feeding  they  do 
not  leave  the  case,  but  reach  out 

Fig.    482.— The    cases    of    the    cigar  ^s  far  as  possible  from  it.      As 
case-bearer:  a,   upper   view   oi    the  ,     . 

cigar-shaped  case;  showing  the  they  grow  they  enlarge  their 
smooth  and  the  hairy  sides  and  the  ^ases,  which  finally  assume  the 
three-lobed   hind    opening;    b,    side  +     •  +•  r     ^v. 

view  of  same;  c,  the  case  as  it  appears  shape  characteristic  oi  the 
in    the    spring    with    the    tube-like   gpgcies. 

addition ;  d,  the  fall  and  winter  case —        rr-n     '       r    i        •  i_ 

much  enlarged.  (After  Hammar,  Those  of  the  Cigar  case-bearer 
U.  S.  Dept.  Agr.)  are    straight    and    resemble   a 

miniature  cigar,  being  of  a  brown  color  and  composed  of  bits 
of  leaf  bound  together  with  silk.  The  cases  of  the  pistol  case- 
bearer  resemble  an  old-fashioned  pistol  in  shape,  the  butt  being 
at  the  upper  end,  and  are  blackish,  being  composed  of  excrement 
and  silk.  As  the  caterpillars  become  larger  they  devour  the  entire 
leaf,  except  the  midrib  and  large  veins,  and  also  attack  the  flower 
buds,  flowers  and  fruit.  The  larvae  of  the  cigar  case-bearer  be- 
come full  grown  about  the  middle  of  June  in  New  York,  when 
they  migrate  to  the  twigs,  where  they  attach  their  cases  firmly  to 
the  bark  and,  turning  around  so  that  their  heads  are  outward. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR         549 

transform  to  pup«.  The  pupal  stage  lasts  ten  or  twelve  days,  most 
of  the  moths  emerging  in  early  July.  The  pistol  case-bearers 
become  full  grown  and  transform  about  a  month  earher.  The 
adults  of  both  species  are  Uttle  grayish  moths  with  wings  expand- 
ing about  one-half  inch,  and  broadly  fringed  with  long  hairs. 
The  eggs  of  both  species  are  laid  singly  on  the  under  sides  of  the 
leaves  and  hatch  in  ten  days  to  two  weeks.  The  young  cater- 
pillars which  hatch  from  them  feed  within  the  leaf  for  a  short  time 
as  leaf-miners,  before  they  make  their  little  cases  and  migrate  to 
the  twigs,  where  they  remain  until  spring. 


Fig.  483. — Apple  leaf  with  cigar  case-bearers  at  work — natural  size.     (After 
Hammar,  U.  S.  Dept.  Agr.) 

Control. — Spraying  with  Paris  green  or  arsenate  of  lead  just 
before  the  leaf  buds  open  and  again  as  soon  as  the  foliage  is  out, 
will  destroy  the  httle  caterpillars. 

The  Bud  Moth  * 

This  is  a  European  species  which  was  first  noted  in  this  country 

in  1841,  and  has  since  spread  throughout  the  Northern  and  Middle 

*  Tmetocera  ocellana  Schiff.  Family  TortricidoB.  See  M.  V.  Slingerland, 
Bulletin  107,  Cornell  Univ.  Agr.  Exp.  Sta.;  W.  E.  Britton,  9th  Report,  State 
Entomologist  of  Connecticut,  p.  353. 


550      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

States  east  of  the  Rocky  Mountains  and  to  Oregon  and  Idaho. 
The  larvse  feed  on  all  of  the  common  deciduous  fruit  trees,  and 
blackberry,  but  are  most  commonly  injurious  to  apple.  The 
adult  moth  is  a  dark  ash  gray  with  broad  yellowish  bands  across 
the  fore-wings,  which  expand  about  five-eighths  inch.  The 
full-grown  caterpillar  is  one-half  inch  long,  of  a  light  chestnut- 
brown  color,  with  the  head,  legs  and  thoracic  shield  dark  brown 
or  black,  smooth  and  shiny. 

Life  History. — The  larvse  hibernate  in 

small,  oval,  silken  cases   attached   to   the 

bark  of  a  twig.     About  the  time   the  buds 

begin  to  swell  in  the  spring,  the  caterpillars 

Fig.  484.— The  bud  moth  t>ore  into  them,  thus  early  protecting  them- 

{Tmetoceraocellana  selves    from    insecticides.     As    the  young 

Schiff.) — twice  natural  <•  ^^      ,x.  -        -n 

size.      (After    W.  E.  leaves  and  flowers  untold,    the    caterpillars 

Britton.)  form  nests  for  themselves  by  tjdng  the  leaves 

together,  and  destroy  the  young  fohage  and  flower  buds,  but  do 
not  leave  the  nests  in  feeding.  In  New  York,  they  become  full 
grown  during  June, 
and  transform  to 
pupse  in  the  silk-lined 
nests.  About  ten 
days  later  the  moths 
emerge  and  lay  the 
eggs    singly    or    in 

small  clusters  on  the  W|  VEI^'' 

under  surface  of  the 
leaves.  The  egg  is 
disk-like,  much  flat- 
tened, usually  oval 
in  shape,  and  trans- 
parent, resembUng  a 
minute  drop  of 
water.  The  eggs 
soon  hatch  and  the  Fig.  485. — Young  apple  leaves  in  fested  by  the 
young      caterpiUars  ^ud  moth  larva.     (After  W.  E.  Britton.) 

feed  on  the  under  sides  of  the  leaves,  protecting  themselves  by  a 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 


551 


thin  silken  web.     In  the  fall  they  migrate  to  the  twigs  and  form 
the  small  silken  cases  in  which  they  pass  the  winter. 

Control.— Dr.  Britton  reports    that    the  caterpillars  may  be 


Fig.  486. —  Apple  leaf  injured  by  the  bud  moth  caterpillar — natural  size. 
(After  W.  E.  Britton.) 

effectively  destroyed  by  spraying  with  arsenate  of  lead  1  pound 
tc  10  gallons,  which  should  be  applied  just  as  the  buds  are  bursting 
and  agam  before  the  trees  blossom. 


552       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Codling  Moth  * 

The  common  apple  worm,  the  larva  of  the  codling  moth,  is 
probably  the  best  known  and  most  generally  destructive  of  all 
the  apple  insects.     It  is  an  old  European  insect  and  has  been 


Fig.  487. — ^The  codling  moth  (Cydia  pomonella  Linn.) :  a,  egg — greatly  enlarged; 
b,  young  larva  hatching  from  egg;  c,  larva  in  winter  cocoon  on  inside  of  a 
bit  of  bark;  d,  pupa — original;  e,  moth — after  Slingerland — all  much 
enlarged. 

distributed  to  almost  all  parts  of  the  world  where  apples  are 

grown.     The  "wormy"  apple  is  so  well  known  that  the  work 

of  the  larva  needs  no  description,  but  the  aggregate  loss  which 

it  occasions  is  not  always  appreciated,  as  most  of  the  injured 

fruit  drops  and  no  account  is  kept  of  the  windfalls,  and  if  the  picked 

*  Cydia  pomonella  Linn.  Family  Tortricidae.  See  A.  L.  Quaintance. 
Yearbook  U.  S.  Dept.  Agr  ,  1907,  p.  435;  E.  L  Jenne,  Bulletin  80,  Part  I, 
Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  C.  B.  Simpson,  Bulletin  41,  n.  s., 
Div.  Ent.,  U.  S.  Dept.  Agr.;  E.  D.  Sanderson,  Bulletin  143,  N.  H.  Agr.  Exp. 
Sta  ;  and  bulletins  of  the  State  Agricultural  Experiment  Stations.  Laspeyresia 
is  now  said  to  be  the  correct  generic  name,  both  it  and  Carpocapsa  taking 
precedence  over  Cijdia.  However,  as  things  now  stand  any  one  of  the  three 
names  may  be  used. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 


553 


fruit  is  not  seriously  infested  the  grower  does  not  notice  that  he 
has  lost  a  large  part  of  the  crop,  though  where  the  pest  is  abundant 
so  much  of  the  fruit  is  injured  that  but  Kttle  remains  to  be  picked 
on  unsprayed  trees.  In  1907  Professor  Quaintance  estimated 
the  annual  loss  due  to  this  insect  in  the  United  States  at  about 
$12,000,000,  and  this  estimate  must  now  be  about  doubled. 

The  moths  fly  at  dusk  and  Wn 
are  rarely  seen,  as  during  the 
day  they  rest  on  the  bark 
which  they  closely  resemble 
in  color.  The  wings  expand 
about  three-quarters  inch  and 
have  somewhat  the  appear- 
ance of  grayish-brown  watered 
silk,  but  when  more  closely 
examined  are  seen  to  be 
crossed  by  numerous  Unes  of 
gray  and  brown  scales.  Near 
the  hind  angle  of  each  front 
wing  is  a  large  dark  brown 
spot  marked  with  streaks  of 
brown  or  gold.  The  hind- 
wings  are  of  a  lighter  grayish- 
brown  color,  darker  toward  the 
outer  margin. 

Life  History 
passed  by  the  full-grown  larvae 
in   their   small   white    cocoons 


The  winter  is  ^^^-  ^^^' — Cocoons  of  codling  moth  as 
found  attached  to  a  piece  of  loose 
bark — natural  size.  (After  Slinger- 
land.) 


beneath,  or  in  crevices  of,  the  bark.  About  the  time  the  apples 
blossom  the  larvae  transform  to  small  brown  pupae,  from  which 
the  moths  emei'ge  in  two  to  three  weeks.  If  the  evenings  be  warm 
the  females  commence  to  deposit  their  eggs  within  a  few  days, 
laying  most  of  them  on  the  foliage.  A  female  lays  from  60 
to  75  eggs  and  though  most  of  them  are  placed  on  leaves  near 
the  young  fruit,  ofttimes  they  are  deposited  on  limbs  or  trees  with 
no  fruit.  The  individual  egg  looks  much  like  a  small  white 
blister  about  the  size  of  a  pinhead.  It  is  at  first  quite  trans- 
parent, but  later  a  brownish  or  blackish  streak  is  seen,  showing 


554       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


the  little  caterpillar  forming  within.  The  eggs  hatch  in  from  five 
to  ten  days,  depending  upon  the  season  and  temperature,  most 
of  them  hatching  about  three  or  four  weeks  after  the  blossoms 
fall. 

The  young  apple  worm  is  at  first  only  about  one-sixteenth 
inch  long,  of  a  whitish  color,  with  a  shining  black  head,  and 
with  distinct  blackish  tubercles  over  the  body,  which  become 
quite  indistinct  in  later  life.  Upon  hatching  the  young  larva 
usually  feeds  a  little  on  the  tender  parts  of  the  leaves  before 
it  crawls  to  the  nearest  apple,  which  is  probably  8  or  10  inches 


Fig.  489. — Pupa?  of  codling  moth  in  cocoons — enlarged.     (After  Sliiigerland.) 

distant.  Over  90  per  cent  of  the  larvae  enter  the  apples  through 
the  blossom  end  and  feed  a  little  within  the  calyx  before  they  bore 
inward  to  the  core.  The  others  enter  at  the  stem  end  or  at  the 
side,  where  a  leaf  may  touch  the  apple.  The  seeds  of  the  apple 
seem  to  be  most  relished,  for  the  larva  soon  hollows  out  each  of 
them  as  well  as  the  surrounding  core,  its  work  being  indicated 
by  the  well-known  excreta  thrown  out  from  the  calyx,  showing 
the  "worminess"  of  the  apple.  The  larva  becomes  full  grown 
in  from  three  to  four  weeks  and  eats  it  way  out  through  the  side 
of  the  apple,  leaving  a  round  exit  hole,  and  seeks  a  place  to  form 
its  cocoon.  The  full-grown  caterpillar  is  about  three-quarters 
inch  long,  whitish  or  pinkish  in  color,  with  a  brown  head  and 
faint  tubercles  over  the  body,  and  with  three  pairs  of  thoracic 
legs  and  five  pairs  of  abdominal  prolegs.  The  cocoons  are  found 
mostly  on  the  trunks  of  the  trees,  as  in  winter.  The  pupal  stage 
of  the  first  summer  generation  lasts  ten  to  twelve  days,  and 
the  moths  emerge  about  eight    weeks  after  the  eggs  were  laid. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR        555 


In  northern  New  England  but  2  or  3  per  cent  of  the  larvae 
pupate,  the  majority  hibernating  over  winter,  so  that  there  is 
but  a  small  second  generation. 
Farther  south  a  large  number 
transform  and  in  the  Middle 
States  there  are  two  full  gene- 
rations. In  the  far  South,  as  in 
Georgia,  Arkansas  and  New 
Mexico,  there  are  three  gene- 
rations. In  any  event  the 
larvae  leave  the  apples  in  the 
fall  and  hibernate  in  their 
cocoons,  those  but  partly 
grown  usually  dying  before 
spring.  The  life  cycle  of  the 
second  and  third  generations 
are  essentially  the  same  as 
that   of   the   first,  except  that 


Fig.  490. — Pupa  skin  of  codling  moth 
remaining  attached  to  cocoon — en- 
larged. 


a  large  proportion  of  the  eggs  are  laid  on  the  fruit  and  more  of 
the  larvae  enter  the  apples  through  the  sides  or  stem  end.  The 
work   of   the   larvae    of    the    later    broods    is     also    somewhat 

different,  as  much  of  it  con- 
sists of  eating  around  the 
blossom  end  or  on  the  face 
of  the  apple,  eating  out  small 
holes  or  tunneling  under  the 
skin,  as  shown  in  Fig.  496. 
"V\Tien  two  or  three  genera- 
tions occur,  the  injury  by 
them  often  becomes  very 
severe  if  the  first  generation 
has  not  been  largely  destroyed 
b}^  thorough  spraying.  Very  similar  injury  is  done  by  the  larva  of 
the  lesser  apple  worm,*  which  is  very  difficult  to  distinguish,  but 
fortunately  the  same  treatment  will  control  both  pests. 

Control. — Scraping  the  loose  bark  from  the  trees  and  keeping  the 
bark  smooth  removes  the  favorable  conditions  for  the  hibernation 

*  Enarmonia  prunivora  Walsh.  Family  Tortricidae.  See  A.  L.  Quaintance, 
Bulletin  68,  Part  V,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  Foster  and 
Jones,  Bulletin  80,  Part  III,  ibid. 


Fig.  491. — Young  larva  of  codling  moth 
in  calyx  cavity  of  apple — enlarged. 


556         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


of  the  larvae.     A  large  proportion  of  the  hibernating  larvae  are  de- 
stroyed by  woodpeckers  and  nut-hatches  during  the  winter  and 

they  should  be  attracted  to  the  orchards 
by  hanging  up  bones  and  suet.  Pick- 
ing up  the  fallen  apples  and  destroying 
them  before  the  larvae  have  left  them  to 
form  their  cocoons  will  do  much  to 
lessen  the  numbers  and  will  aid  in 
the  control  of  other  insects.  Cellars  and 
storage  houses  where  apples  are  kept 
over  winter  should  be  screened  to  pre- 
vent the  exit  of  the  moths  in  the  spring. 
The  principal  method  of  control,  how- 
ever, is  in  spraying  with  arsenicals, 
which,  when  properly  done,  will  destroy 
practically  all  of  the  larvae.  Although 
Paris  green  and  arsenite  of  lime  have  long 
been  used  for  this  purpose,  arsenate  of 
lead  is  now  preferred  on  account  of  its 
superior  adhesive  quahties  and  because 
there  is  less  danger  of  burning  the  foliage 

FiG.492.-Larvaofthecod-  with  it.     Where   Bordeaux   mixture    is 
ling   moth    only  a    few 
days  old,  showing  tuber- 
cles—  much     enlarged. 
(After  Slingerland.) 

sprayed  for  fungous  dis- 
eases at  the  same  time 
Paris  green  may  be  ap- 
plied with  it  and  the 
Bordeaux  will  cause  it  to 
adhere  as  well  as  arsen- 
ate of  lead  and  there  will 
be  little  danger  of  burn- 
ing with  a  good  quality 
of  Paris  green .  One-third 
pound  per  barrel  of  Paris 
green,  2  or  3  pounds  of  Fig.  493.-Full  grown  larva  of  the  codling  moth 
^         '  ^  — enlarged  about  three  times.  (After  felmg- 

arsenate    of   lead,    or   1        land.) 

quart  of  stock  solution  of  arsenite  of  lime  are  the  proper  strengths 
for  general  use.     The  first  spraying  for  the  codling  moth  should 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 


557 


be  given  just  after  the  blossoms  have  fallen  and  before  the 
sepals  of  the  calyx  close,  the  object  being  to  place  the  poison 
in  the  calyx  cavity  so  that  the  Mttle  larva  will  be  poisoned  when  it 


Fig.  494. — Young  apples  in  right  condition  to  spray  for  the  codling  moth 
and  with  calj^x  sepals  closed  too  far  for  effective  sprayQig.  (After  Quaint- 
ance,  U.  S.  Dept.  Agr.) 

enters  and  feeds  in  the  calyx  a  few  weeks  later.     In  general  this 
spraying  should  be  given  within  a  week  or  ten  days  after  two- 


FiG.  495. — Work  of  the  first  generation  of  codling  moth  larva. 

thirds  of  the  petals  have  dropped,  but  the  time  will  depend  upon 
the  variety  and  the  season. 

In  the  West  great  emphasis  has  recently  been  placed  upon 


558        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


using  a  coarse  spray  with  a  high  pressure,  100  to  250  pounds, 
which  will  drive  the  spray  through  the  bases  of  the  stamens 
into  the  lower  calyx  cavity,  and  though  excellent  results  are 
undoubtedly  secured  in  this  way,  experiments  in  the  East  indicate 
that  a  mist  spray  is  equally  effective  if  thoroughly  applied, 
whether  the  lower  calyx  cavity  is  reached  or  not.  There  is  no 
question,  however,  of  the  importance  of  maintaining  a  good 
pressure,  of  at  least  100  pounds,  so  that  the  spray  may  be  forced 
through  the  foliage;  for  the  blossoms  point  in  all  directions, 
and  the  spray  must  be  forced  through  the  tree  to  reach  those 
pointing  inward  on  the  opposite  side.     An  angle  on  the  end  of 


Fig.  496. — Work  of  the  second  generation  of  codling  moth  larvse. 

the  spray-rod  which  will  turn  the  nozzle  at  35  or  45  degrees  will 
greatly  aid  in  reaching  all  parts  of  the  tree. 

The  second  spraying  should  be  applied  three  or  four  weeks 
after  the  blossoms  fall,  just  as  the  eggs  are  hatching.  At  this 
time  the  object  should  be  to  cover  the  foliage  thoroughly,  so 
that  the  young  larvae  may  be  killed  while  they  feed  on  the  foliage. 
Consequently  both  the  upper  and  under  surfaces  of  the  leaves 
should  be  coated.  If  the  first  spraying  has  been  well  done,  the 
second  will  often  be  unnecessary  where  there  is  but  a  partial 
second  brood  or  where  the  pest  is  well  under  control,  but  as  it 
is  often  necessary  to  spray  for  the  fungous  diseases  at  this  time 
it  is  well  to  add  the  arsenical,  which  but  slightly  increases  the 
cost.  Where  there  is  a  full  second  generation,  as  in  most  of  the 
Middle  and  Pacific  States,  a  third  application  as  the  second 
generation  of  larvae  are  hatching,  will  be  found  advisable  about 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR  559 

nine  or  ten  weeks  after  the  petals  fall,  and  a  fourth  two  or  three 
weeks  later  may  be  necessary.  With  thorough  spraying  not 
over  1  or  2  per  cent  of  the  picked  fruit  should  be  wormy,  as 
most  of  the  wormy  fruit  will  drop  early  in  the  season. 

Recent  experiments  have  shown  that  quite  as  effective  codling 
moth  control  can  be  secured  by  dusting  with  powdered  arsenate 
of  lead  with  sulphur  as  the  carrier.  Some  of  the  advantages  of 
dusting  are  discussed  under  the  description  of  the  dusting  practice 
in  an  early  chapter. 

The  Apple-maggot  or  "  Railroad  Worm  "  * 

The  apple-maggot  has  long  been  known  as  the  worst  pest  of 
summer  and  fall  apples  in  the  New  England  States,  and  has 
extended  its  injuries  to  eastern  New  York  and  southeastern 
Canada.  It  has  been  recorded  from  Michigan,  Wisconsin,  Illinois, 
Minnesota,  New  Jersey,  and  Pennsylvania,  but  seems  to  be  only 
occasionally  injurious  there,  though  it  has  been  reared  from 
haws  in  Illinois  and  Wisconsin,  which  would  indicate  that  the 
insect  is  native  in  those  States.  Evidently  it  is  widely  distributed 
throughout  the  northeastern  United  States,  but  for  some  reason 
is  most  injurious  in  New  England.  The  fruit  is  injured  by  the 
small  white  maggots,  which  burrow  through  the  flesh,  leaving 
discolored  streaks  through  it,  often  becoming  so  numerous  as 
entirely  to  honeycomb  the  pulp  which  breaks  down  into  a  yellowish 
mass  merely  held  together  by  the  skin.  An  apple  quite  fair 
exteriorly  will  often  be  found  to  be  almost  completely  "rail- 
roaded" by  the  maggots,  although  brown,  shghtly  sunken 
streaks  in  the  skin  usually  indicate  their  presence.  Sweet  and 
subacid  varieties  of  summer  and  early  fall  apples  are  worst  injured, 
but  where  the  pest  develops  unchecked,  winter  sorts,  such  as  the 
Baldwin  and  particularly  the  Northern  Spy,  are  often  seriously 
injured. 

The  parent  of  the  maggot  is  a  httle  fly  slightly  smaller  than 
the  house-fly,  of  a  blackish  color,  with  yellowish  head  and  legs, 

*  Rhagoletis  pomonella  Walsh.  Family  Trypetidoe.  See  A.  L.  Quaintance 
Circular  101,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  F.  L.  Harvey,  Report 
Maine  Agr.  Exp.  Sta.,  1889,  p.  190;  W.  C.  O'Kane,  Journal  of  Economic 
Entomology,  IV,  173,  and  Bulletin  N.  H.  Expt.  Sta.  No.  171,  also  H.  H.  P. 
Severin,  Bulletin  251,  Maine  Agr.  Expt.  Sta. 


560        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


greenish  eyes,  and  three  or  four  white  bands  across  the  abdomen. 
The  wings  are  marked  by  four  black  bands,  as  shown  in  Fig.  497, 
which  distinguish  it  from  similar  flies  found  on  apples. 

Life  History. — The  flies  emerge  during  July  in  New  England 
and  live  for  several  weeks.  The  females  at  once  commence 
depositing  their  eggs  in  the  early  varieties  of  apples.  The  eggs 
are  laid  just  under  the  skin  in  a  vertical  position,  on  the  cheek  of 
the  apple.  The  egg  is  elhptical,  about  one-thirtieth  inch  long, 
and  yellowish  in  color.  A  female  will  lay  300  to  400  eggs,  12 
or  15  often  being  placed  in  a  single  apple.  The  eggs  hatch  in 
four  or  five  days  and  the  little  maggots  at  once  burrow  into  the 
pulp.  By  means  of  a  vertical  motion  of  the  head  they  rasp  the 
pulp  with  the  small,  black  hook-like  mouth  parts,  and  in  less  than 


Fig.  497. — ^The  apple-maggot  {Rhagoletis  pomonella  Walsh):  a,  adult;  b, 
larva  or  maggot;  c,  funnel  of  spiracle  on  head;  d,  puparium;  e,  portion 
of  apple  showing  injury  by  maggots;  a,  b,  d — enlarged;  e — reduced. 
(After  Quaintance,  U.  S.  Dept.  Agr.) 

a  minute  can  tunnel  their  own  length.  They  become  full  grown 
in  four  to  six  weeks  during  the  summer,  but  if  only  partly  grown 
when  winter  sets  in,  many  of  them  seem  to  hibernate  until  spring. 
The  mature  maggot  is  about  one-third  inch  long,  yellowish-white, 
footless,  much  Hke  similar  maggots,  and  distinguishable  by  the 
microscopic  characters  of  the  spiracles  of  the  first  and  last  seg- 
ments. The  mature  maggot  goes  just  beneath  the  surface  of  the 
ground,  where  its  skin  hardens  to  a  puparium  in  which  the  pupa 
is  formed,  in  which  stage  the  winter  is  passed.  In  barrels  or 
storage   places   the   maggots   pupate   beneath   the   apples,    and 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR  561 

occasionally  a  puparium  is  found  in  the  burrow  of  the  maggot 
within  an  apple.  Most  of  the  puparia  are  within  1  or  2  inches  of 
the  surface.  There  is  but  one  generation  a  year.  Some  of  the 
pupae  do  not  emerge  the  next  spring  but  remain  dormant  for  an 
entire  year  in  addition  to  the  usual  hibernating  period,  so  if  all 
the  active  individuals  were  killed  one  year  there  would  still  be 
emerging  adults  the  following  spring. 

Control. — As  most  of  the  affected  fruit  drops  to  the  ground, 
during  summer  it  should  be  picked  up  twice  a  week  and  destroyed 
before  the  maggots  have  left  it  to  pupate.  Where  this  is  carefully 
done  injury  by  the  pest  is  greatly  reduced.  Particular  attention 
should  be  given  to  the  destruction  of  infested  summer  apples. 
Hogs  pastured  in  the  orchard  will  do  this  work  admirably,  and 
where  there  are  but  a  few  trees  on  bare  or  cultivated  ground 
chickens  will  destroy  the  larvae.  Plowing  the  orchard  deeply 
as  early  as  feasible  in  spring  and  keeping  it  well  cultivated  in  early 
summer  will  bury  the  puparia  so  as  greatly  to  lessen  injury,  which 
is  always  worse  in  uncultivated  sod  orchards.  Poisoned  syi'ups, 
sprayed  onto  the  trees  to  attract  the  flies,  have  given  good 
protection  from  the  maggot  but  have  scorched  foliage  on  account 
of  the  use  in  them  of  a  soluble  form  of  arsenic.  This  method 
of  treatment  must  be  considered  as  still  in  the  experimental  stage. 

The  Apple  Curculio  * 
The  apple  curculio  has  been  commonly  confused  with  the  plum 


a 

Fig.  498. — The  apple  curculio  {Anthonomus  quadrigibbus  Say):  a,  b,  adult 
beetles;  c,  larva;  d,  pupa — all  enlarged.     (After  Riley.) 

curculio,  but  is  by  no  means  as  common  or  injurious,  and  is 
quite  distinct  in  both  appearance  and  habits.     The  adult  beetle 

*  Anthonomus  quadrigibbus  Say.  Family  Curculionidce.  See  C.  S. 
Crandall,  Bulletin  98,  111.  Agr.  Exp.  Sta.,  p.  514;  F.  E.  Brooks,  Bulletin  126, 
W.  Va.  Agr.  Exp.  Sta.,  p.  113. 


562      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


■v-^ 


is  about  the  same  size  as  the  plum  curculio,  but  more  reddish- 
brown  in  color,  the  abdomen  is  more  robust,  and  the  wing-covers 
bear  four  prominent  humps,  the  anterior  being  much  larger  than 
those  on  the  plum  curculio.     The  snout  of  the  apple  curculio  is 

as  long  as  the  rest  of  the  body 
and  is  held  straightforward  from 
the  head,  instead  of  hanging 
down  as  does  the  snout  of  the 
plum  curculio.  The  work  of  the 
apple  curculio  is  also  different 
in  that  after  laying  the  egg  in  a 
small  cavity  in  the  fruit,  on 
crescent-shaped  mark  is  made 
around  it.  The  apple  curculio  is 
a  native  species  which  breeds 
in  wild  haw,  wild  crab,  and 
wild  cherry,  and  has  been  reared 
in  plum,  quince  and  pear. 
"It  has  been  reported  from 
Connecticut  and  Ontario  south  to 
North  Carolina  and  westward  as 
far  as  New  Mexico.  It  seems 
to  have  been  more  troublesome 
in  Missouri,  Illinois  and  other 
mid-western  States  than  else- 
where," but  has  never  done  any- 
thing like  the  injury  due  to  the 
plum  curculio  and  can  hardly  be 
regarded  as  a  serious  pest. 

Life    History. — The     beetles 
commence  laying  eggs    in    the 

punctures  from  the  surface  and  in    f  j-uit  SOOn  after  the  blossoms  drop 

section.     (After  C.  S.  Crandall.)  ,         ,  •         ^  ■   a    e   x  ,+„ 

*"  '       and  contmue  for  a  period  of  Sixty 

days,   an   individual   female   laying   about   65   eggs.     The   eggs 

hatch  in  about  five  days  and  the  larvse  feed  on  the  flesh  of  the 

apple  for  about  twenty  days,  when  they  transform  to  pupae  within 

the  fruit.  A  week  later  the  beetles  emerge,  but  feed  very  Kttle  during 

the  late  summer  before  they  enter  hibernation  for  the  winter. 

most  of  them  leaving  the  trees  by  the  latter  part  of  August. 


Fig.  499. — Work  of  the  apple  curcuho; 
a,  a' ,  c,  c',  feeding  punctures  from 
the  surface  and  in  section;  b,  b',  egg 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR         563 

The  larva  is  a  footless,  whitish  grub  a  half  inch  long  when  full 
grown  with  a  hump-backed  appearance  due  to  the  enlargement 
of  the  anterior  abdominal  segments,  which  prevents  the  larva 
from  straightening  out.  The  beetles  injure  the  fruit  by  puncturing 
it  for  feeding  and  for  the  deposition  of  eggs,  causing  it  to  become 
dimpled  and  gnarled  as  does  the  plum  curculio,  and  the  larvae  feed 
within  the  fruit,  mining  the  flesh,  in  which  they  undergo  their 
complete  development. 

Control. — Thickets  of  wild  crab  or  hawthorn  trees  should  be 
destroyed  wherever  near  an  orchard,  for  the  beetles  will  breed  in 
their  fruit  and  then  migrate  to  the  orchard.  Jarring  as  for  the 
plum  curculio  may  be  practiced  on  young  trees,  and  spraying  as 
for  that  species  will  doubtless  largely  reduce  the  injury.  Usually 
this  insect  is  not  sufficiently  injurious  to  warrant  special  treatment 
where  its  native  food-plants  are  not  overabundant  near  the 
orchard. 

The  Pear  Leaf  Blister-mite  * 

The  pear  leaf  blister-mite  has  long  been  known  as  a  pest  of  pear 
foliage  wherever  the  pear  is  grown,  and  has  similarly  affected  apple 
foliage  in  Europe,  but  only  in  recent  years  has  it  become  a  serious 
pest  of  apple  fohage  in  New  York,  New  England,  Ontario  and 
Pennsylvania.  Just  why  it  should  suddenly  become  an  apple 
pest  after  having  occurred  in  this  country  for  years  without 
noticeably  injuring  it  is  a  mystery,  though  dry  seasons  may 
possibly  be  accountable  for  it. 

The  work  of  the  mites  is  recognized  by  reddish  blisters  forming 
on  the  young  foliage,  which  later  turn  blackish  and  have  a  corky 
texture.  Badly  affected  leaves  drop,  so  that  a  tree  is  often  largely 
defoliated,  and  where  the  mites  are  abundant  they  attack  the 
young  fruit. 

The  mites  are  not  true  insects,  as  they  belong  to  the  same  class 
as  the  spiders,  scorpions,  and  ticks.  One  of  the  more  common 
larger  mites  is  the  red  spider  of  greenhouses,  which  affects  flower- 
ing plants,  vegetable  crops,  and  fruits  of  all  sorts.  These  little 
blister-mites  are  of  microscopic  size,  only  1-100  to  1-200  inch  in 
length,  so  that  they  can  be  seen  only  with  a  lens,  and  must  be 

*  Eriophyes  pyri  Pgst.  Class  Arachnida.  Order  Acarina.  Family 
EriophyidoE,  with  which  are  associated  several  nearly  related  species  with 
similar  habits.  See  Parrott,  Hodgkiss  and  Schoene,  Bulletins  283  and  306, 
N.  Y.  Agr.  Exp.  Sta. 


564       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

examined  with  a  compound  microscope  to  distinguish  the  species. 
One  is  shown  much  magnified  in  Fig.  500.  They  are  elongate, 
with  two  pairs  of  legs,  and  slender  abdomens,  composed  of  50 
to  80  small  rings,  frequently  marked  with  rows  of  small  tubercles 
and  ornamented  with  a  few  hairs  and  bristles. 

Life  History. — The  mites  spend  the  winter  in  the  buds,  and 
as  warm  weather  approaches  in  the  spring  they  become  active 
and  move  toward  the  base  of  the  growing  bud  scales  and  feed 
there.  As  the  young  leaves  unfold  the  mites  migrate  to  them. 
They  burrow  through  the  surface  of  the  leaf  and  feed  upon  the 
succulent  tissue  within,  setting  up  an  irritation  which  soon  results 
in  reddish  spots  on  the  surface.  Within  these  mines  the  eggs 
are  laid,  as  many  as  14  having  been  found  in  a  single  blister. 
The  young  hatch  in  about  a  week  and  burrow  around  in  all 


Fig.  500. — The  pear  leaf  blister-mite  (Eriophyes  pyri  Pgst.) :  highly  magni- 
fied.    (After  Parrott.) 

directions,  feeding  on  the  tissues  and  juices.  When  full  grown 
they  leave  the  gall  through  small  openings  in  the  under  surface 
and  start  new  colonies  which  produce  similar  galls.  They  con- 
tinue to  reproduce  and  migrate  throughout  the  summer,  and  under 
favorable  conditions  become  numerous  enough  to  completely 
infest  the  new  leaves  as  they  appear.  In  the  fall  they  leave  the 
leaves  to  hibernate  in  the  buds  as  already  described. 

On  pear  the  blisters  are  at  first  greenish  pimples,  which  become 
reddish  and  later  brilliant  red  blisters,  and  finally  they  become 
brown  or  black  and  the  tissue  corky.  When  numerous  the 
galls  coalesce,  forming  dark  brown  patches  over  the  leaf,  which 
often  break  open,  particularly  along  the  edges  of  the  leaves. 
On  the  blossom  ends  of  the  fruit  and  on  the  stems  they  produce 
light-colored  pimples,  which  do  not  seem  to  injure  the  fruit. 
On  apple  the  bhsters  are  less  brilUantly  colored  than  on  pear, 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 


565 


and  become  a  light  brown  or  dark  green  color  on  the  upper  leaf 
surface  and  uniformly  brown  beneath,  looking  something  like 
the  work  of  the  ai)ple  rust.  The  young  fruit  is  sometimes  attacked, 
on  which  small  green  pimples,  which  later  make  blister-like  spots 
or  pock  marks,  are  made  toward  the  blossom  ends,  but  which 
do  not  seem  to  cause  much  damage. 


Fig.  501. — Old  leaf  cluster  wiili  galls  of  pear  leaf  blister-mite  on  apple  fruit 
and  leaves.     (After  Parrott,  Hodgkiss  and  Schoene.) 

Control. — The  mites  may  be  controlled  by  spraying  with 
10  per  cent  kerosene  emulsion,  miscible  oils,  or  lime-sulfur  wash 
used  the  same  as  for  the  San  Jose  scale.  Spraying  should  be 
done  in  October  or  November  as  soon  as  possible  after  a  majority 
of  the  leaves  have  fallen,  as  many  of  the  mites  are  still  in  the 
pubescence  of  the  young  wood,  where    they  are  more  easily  de- 


566       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

stroyed  than  when  under  the  bud  scales.  In  spring  spray  just 
as  the  buds  begin  to  break  and  show  the  tips  of  the  young  leaves; 
spraying  later  than  this  will  injure  the  foliage,  and  earlier  spraying 
is  not  as  effective.  By  using  lime-sulfur  in  the  spring,  the  usual 
treatment  with  Bordeaux  mixture  for  diseases  at  that  time  is 
rendered  unnecessary.  Where  infestation  is  serious  both  fall  and 
spring  sprayings  should  be  given ;  otherwise  the  fall  spraying  is  the 
better.  The  buds  and  new  growth  should  be  thoroughly  drenched, 
while  the  rough  bark  of  the  trunk  and  old  limbs  may  be  neglected 
as  far  as  the  mites  are  concerned.  Where  pear  trees  are  but 
sHghtly  infested,  the  spread  of  the  pest  may  often  be  prevented 
by  simply  pruning  out  and  burning  the  infested  twigs  upon  the 
first  appearance  of  injury. 

The  Pear  Psylla  * 

Where  the  pear  psylla  is  abundant,  pear  growers  have  come 
to  fear  it  next  to  the  San  Jose  scale,  and  until  recently  owners 


Fig.  502. — The  pear  psylla  (Psylla  pyricola  Foerst):  adult,  fuU-growTi  nymph 
and  egg — all  greatly  enlarged  in  different  proportions.  (After  Slinger- 
land.) 

in  eastern  New  York  became  so  discouraged  in  their  attempt  to 

control  it  that  orchards  were  cut  down.     It  is  an  old  European 

pest  and  was  first  noted  in  Connecticut  in  1832,  since  when  it  has 

spread  southward  to  Maryland  and  Virginia  and  westward  to 

Michigan  and  Illinois,  in  which  States  it  has  done  considerable 

injury.     The  psyllas  are  nearly  related  to  the  plant-lice  and  are 

*  Psylla  pyricola  Foerst.  Family  Psyllidoe.  See  M.  V.  Slingerland, 
Bulletins  44  and  108,  Cornell  Univ.  Agr.  Exp.  Sta. ;  C.  L.  Marlatt,  Circular 
7,  Div.  Ent.,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR  567 

sometimes  called  jumping  plant-lice,  on  account  of  the  habit  of 
the  adults  of  giving  a  quick  jump  and  flying  from  the  foliage 
when  disturbed.  Like  the  plant-lice  they  reproduce  very  rapidly 
and  suck  the  juices  from  the  foliage  and  fruit.  Usually  the  first 
indication  of  the  pest  is  the  prescence  of  large  quantities  of  honey- 
dew,  secreted  by  the  nymphs,  with  which  the  foliage  becomes 
covered,  and  which  attracts  numerous  ants.  When  the  psyllas 
are  numerous  the  leaves  and  fruit  become  coated  with  this  sticky 
substance  and  it  even  drops  from  them  like  rain  and  runs  down 
the  trunk.  A  blackish  fungus  grows  on  the  honey-dew  and  is 
always  a  good  indication  of  the  presence  of  the  psylla. 

Badly  infested  trees  are  so  injured  by  loss  of  sap  that  they 
shed  their  leaves  in  midsummer,  the  lower  ones  being  the  first 
to  turn  yellow  and  drop.  The  young  fruit  also  drops  from  badly 
infested  trees,  w^hich  make  but  little  growth,  as  the  young  shoots 
are  often  attacked  and  wither  early  in  the  season. 

The  adult  psylla  is  about  one-tenth  inch  long,  of  a  reddish- 
crimson  color  with  brownish-black  markings,  bronzy  eyes  and 
dark  wing-veins,  looking  very  much  like  a  miniature  cicada  or 
dog-day  harvest-fly. 

Life  History. — The  adults  hibernate  over  winter  in  crevices 
of  the  bark  and  there  lay  their  eggs  late  in  April  or  early  May 
on  the  twigs  or  around  the  buds.  The  egg  is  about  one-eighteenth 
inch  long,  hardly  perceptible  without  a  lens,  and  orange-yellow 
in  color.  It  is  pear-shaped  with  the  small  end  drawn  out  into 
a  long  thread,  and  the  larger  end  is  attached  to  the  bark  by  a 
short  stalk  (Fig.  502).  The  later  generations  deposit  the  eggs 
on  the  leaves  often  in  rows  or  bunches.  The  eggs  hatch  in  two 
to  three  weeks  and  the  young  nymphs  feed  on  the  leaf  petioles 
in  the  axils  of  the  leaves  and  later  on  the  leaves,  young  fruit  and 
tender  shoots,  from  which  they  suck  the  sap.  The  nymph  is  a 
peculiar-looking  little  bug,  broadly  oval,  flattened,  of  a  yellowish 
color,  with  crimson  eyes,  but  later  becomes  reddish  with  black 
markings  and  conspicuous  black  wing-pads,  as  shown  in  Fig.  502. 
They  move  very  slowly  and  are  frequently  quite  covered  by  their 
own  honey-dew.  After  molting  some  four  or  five  times,  they 
finally  transform  to  adults  in  about  a  month.  According  to 
Slingerland  there  are  four  generations  in  New  York  and  probably 
five  in  Maryland. 


568         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Control. — As  the  adults  hibernate  over  winter  in  the  bark 
the  treatment  advised  for  the  pear  leaf  bhster-mite  furnishes  the 
best  means  of  control  for  the  psylla,  and  winter  treatment  is 
absolutely  essential  for  its  successful  control.  Otherwise,  the 
best  time  to  spray  is  in  the  spring  just  after  the  eggs  have  hatched 
and  before  the  nymphs  have  secreted  much  honey-dew.  If 
winter  or  spring  spraying  has  been  neglected,  the  trees  should  be 
thoroughly  sprayed  with  "Black-leaf  40"  one  to  1000  with  soap 
added.     Spraying  should  be  done  after  a  shower,  which  will  wash 

much  of  the  honey-dew  off, 
as  the  chief  difficulty  in  sum- 
mer spraying  is  to  reach  the 
nymphs  through  the  thick 
coating  of  honey-dew  with 
which  they  are  covered.  Ob- 
viously the  spray  should  be 
apphed  with  considerable 
pressure  in  a  coarse  spray. 

The  Pear  Thrips* 

The  pear  thrips  has  been 
known  as  an  enemy  of  pears, 
plums,  prunes,  cherries  and 
other  plants  in  Cahfornia 
since  1904  and  within  the 
last  decade  has  been  reported 
from  New  York,  Pennsyl- 
vania, New  Jersey  and  Mary- 
land. It  feeds  on  fruits, 
buds,  flowers  and  leaves  and 
causes  injury  aggregating  at 
least  a  million  dollars  an- 
nually in  California.  The 
insect  is  not  markedly  dif- 
ferent, to  the  casual  observer,  from  the  several  other  species  of 
thrips  discussed  elsewhere  in  this  volume.  Adults  appear  on  the 
fruit  buds  early  in  the  spring  and  lay  their  eggs  on  fruit  and  leaf 

*  TcBnioihrips  pyri  Daniel.  Family  Thripidce.  See  Foster  and  Jones, 
Bulletin  173,  U.  S.  Dept.  of  Agriculture. 


Tme  Pear  Tmaips  (Taeniothai 


Fig.  503.  The  Pear  Thrips  (Tceniothrips 
Pyri  Daniel). — 1. — Adult.  2. — Eggs. 
3. — First-stage  larva.  4. — Full-grown 
larva.  5. — Pupa,  first  stage.  6. — Pupa, 
last  stage.  7. — Side  view  of  head  show- 
ing mouth  parts.  All  greatly  enlarged. 
(After     Foster  and  Jones,  I.e.) 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR  569 

stems  and  young  fruit,  feeding  at  the  same  time  on  growing  parts 
of  the  plant.  Injury  by  the  adults  is  generally  to  the  fruit  buds 
before  blossoming.  The  young  forms  feed  on  fohage  and  fruit 
and  cause  the  defacement  of  fruit  called  fruit  scab  which  greatly 
reduces  the  quaUty,  especially  of  prunes  which  are  the  greatest 
sufferers.  They  remain  inactive  as  fully  grown  nymphs  from 
early  summer  until  the  following  spring  when  the  adults  again 
appear. 

Control. — Since  the  insect  spends  a  large  part  of  the  year  in 
the  soil  in  immature  stages  thorough  cultivation  throughout  the 
summer  may  be  expected  to  destroy  large  numbers.  Spraying 
has  not  given  entire  satisfaction,  but  distillate  oil  emulsions  are 
largely  used  in  California.  These  are  made  by  mixing  30  pounds 
fish  oil  soap,  twenty  gallons  distillate  oil  and  twelve  gallons  of  hot 
water,  by  pumping  them  together  under  high  pressure  through  a 
spray  outfit  into  the  tank.  This  is  stock  solution  and  should  be 
diluted  at  the  rate  of  one  to  twenty.  To  this  should  be  added 
Black-leaf  40,  about  one-half  pint  to  100  gallons  of  the  spray. 
This  is  applied  at  the  time  the  buds  are  bursting  and  may  be 
repeated  after  the  petals  fall.  Spraying  with  thick  whitewash 
gives  some  control  but  the  first  solution  is  preferred.  Any  spray- 
ing treatment  should  be  supplemented  by  Hberal  fertihzation. 

The  Pear  Slug  * 

Not  infrequently  the  foliage  of  pear  and  cherry,  and  occasion- 
ally of  plum  trees  turns  brown  in  midsummer,  which  is  found  to  be 
due  to  small,  slimy,  slug-like  larvae  which  have  eaten  off  the  surfaces 
of  the  leaves.  The  Pear  Slug  is  a  common  pest  throughout  the 
country,  having  been  known  here  for  over  a  century.  It  is  an 
old  European  pest  and  has  become  distributed  to  many  of  the 
British  colonies  in  various  parts  of  the  world.  The  parent  insect 
is  a  small  saw-fly,  about  one-fifth  inch  long,  glossy  black,  with 
four  wings  which  are  iridescent,  with  a  smoky  band  across  the 
middle,  and  which  are  folded  over  the  back  when  at  rest. 

Life  History. — The  flies  are  abroad  by  the  time  the  fohage  is 

well  out,  by  the  middle  of  April  in  Maryland  and  late  May  or  early 

June  in  New  England.     Like  most  of  the  saw-flies  the  female  is 

*  Caliroa  cerasi  Linnaeus.  Family  TenthredinidcB.  See  C.  L.  Marlatt, 
Circular  26,  Div.  Ent.,  U.  S.  Dept.  Agr.,  and  R.  L.  Webster,  Bulletin  130,  Iowa 
Agr.  Expt.  Station. 


570         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


furnished  with  a  strong  ovipositor  with  saw-like  teeth  at  the 
tip,  with  which  she  cuts  a  Uttle  bhster-hke  cell  beneath  the  upper 
surface  of  the  leaf,  in  which  the  egg  is  deposited,  as  shown  in  Fig. 
505.  The  egg  hatches  in  about  two  weeks  and  the  httle  larva 
makes  its  way  out  of  the  cell  through  a  crescent-shaped  cut. 

The  young  larva  is  at  first  nearly  white,  except  the  yellowish- 
brown  head,  but  very  soon  a  slimy  or  gluey  olive-colored  liquid 

exudes  from  over  the 
entire  body,  giving  it 
the  appearance  of  a  min- 
ute slug,  from  which  it 
gets  its  name.  The  head 
is  now  dark  brown,  ap- 
pearing almost  black 
under  the  sHme,  and 
the  body  is  also  darker. 
The  anterior  segments 
are  much  swollen,  con- 
cealing the  head  and  the 
thoracic  legs.  The  ab- 
domen is  furnished  with 
seven  pairs  of  prolegs, 
Fig.  504. — ^The  pear  slug  (Caliroa  cerasi  Lin-  the  usual  pair  on  the 
naeus.) :  a,  adult  female  saw-fly;  b  larva  with  |  ^  g  ^  segment  being 
slime  removed ;  c,  same  m  norma  state;  a,  leaves  .         '^  .° 

with  larvae  natural  size;  a,  6,  c,  much  enlarged,  wantmg  SO  that  the  tip 
(After  Marlatt,  U.  S.  Dept.  Agr.)-  ^f     ^^le     abdomen      is 

slightly  elevated.  The  little  slugs  commence  eating  out  small  bits 
of  the  upper  surface  of  the  leaf,  which  they  gradually  enlarge  un- 
til nearly  the  whole  upper  surface  is  denuded,  leaving  merely  a 
net  work  of  veins,  held  together  by  the  brown  epidermis  of  the 
lower  surface,  which  is  nearly  intact.  Leaves  thus  injured  turn 
brown,  die  and  drop,  so  that  a  tree  will  sometimes  be  nearly  def- 
oliated, except  for  the  new  growth  which  starts  out.  The  larvae 
grow  rapidly,  becoming  full  grown  in  about  twenty-five  days,  when 
they  are  about  one-half  inch  long.  When  full  grown  the  larva 
molts  for  the  fifth  time  and  loses  its  olive-green  slimy  appearance, 
becoming  a  light  orange-yellow  color,  clean  and  dry,  with  a  light- 
colored  head  marked  by  only  the  small  circular  black  eye-spots 
on  the  sides. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 


571 


The  larva  now  enters  the  ground  for  an  inch  or  two,  where 
it  forms  a  small  cell,  which  is  moistened  with  saUva  so  that  the 
walls  become  somewhat  impervious  to  water.  In  six  or  eight 
days  it  transforms  to  the  pupa  and  in  about  two  weeks  after 
the  larva  entered  the  ground  the  adult  fly  digs  its  way  out  of 
the  soil.  Some  of  the  larvae  of  each  generation,  and  all  of  those 
of  the  last  generation  re- 
main in  the  soil  over 
winter  and  transform  to 
pupae  the  next  spring. 
At  Washington,  D.  C,  the 
first  generation  of  larvae 
disappear  by  the  end  of 
June  and  the  second  gene- 
ration, which  is  probably 
followed  by  a  third  gen- 
eration, is  most  abundant 
in  early  July,  when  the 
principal  injury  is  done. 
Farther  north  there  are 
but  two  generations,  the 
second  appearing  in 
August. 

Control. — By  spraying  with  any  of  the  arsenicals  when  the 
work  of  the  slugs  is  first  noticed  on  the  foHage  they  may  be  quickly 
destroyed.  Whale-oil  soap,  or  other  soap,  1  pound  to  4  gallons, 
will  also  destroy  the  larvae  as  a  contact  insecticide.  Hellebore, 
air-slaked  lime,  or  almost  any  finely  divided  dust,  thoroughly 
dusted  over  the  trees  will  also  destroy  most  of  the  larvae,  which 
are  very  readily  killed.  In  gardens  where  water  under  pressure 
is  available,  the  slugs  may  be  washed  off  by  a  jet  from  a  hose, 
as  they  are  frequently  washed  off  by  heavy  rains,  and  are  much 
less  injurious  in  wet  seasons. 


Fig.  505. — Illustrating  method  of  oviposition 
and  emergence  of  the  pear  slug:  a,  cut- 
ting of  cell  beneath  epidermis,  showing  the 
tip  of  the  ovipositor;  6,  the  cell  after  the  egg 
has  been  deposited;  c,  same  after  escape  of 
the  larva — all  much  enlarged.  (After  Mar- 
latt,  U.  S.  Dept.  Agr.) 


The  Tarnished  Plant-bug  * 

The  tarnished   plant-bug  is  one  of  the  most  common  and 

troublesome  plant-bugs  throughout  the  country  from  Canada  to 

*  Lygus  praiensis  Linn.  Family  Capsidoe.  See  Stedman,  Bulletin  47, 
Missouri  Agr.  Exp.  Sta.,  Crosby  and  Leonard,  Bulletin  346,  Cornell  Univ. 
Agr.  Expt.  Station,  and  Leonard  Haseman,  Research  Bulletin  29,  Missouri 
Agr.  Expt.  Station. 


572         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Mexico.  Seemingly  it  is  nearly  omnivorous,  as  it  attacks  almost 
all  of  the  common  garden  crops,  small  fruits,  tender  shoots  of  fruit 
trees  and  young  nursery  trees,  many  flowering  plants,  and  most  of 
our  common  weeds.  It  is  rather  more  important  as  an  enemy 
of  pears  than  on  any  other  crop,  causing  deformation  of  the  fruit 
to  some  extent  every  year  in  some  of  the  important  pear  growing 
regions.  At  the  same  time  it  is  quite  as  common  as  a  garden  pest, 
attacking   a  great   variety  of  garden   crops.     Injury  on   pears 

by  a  bug  of  very  simi- 
lar appearance  is  re- 
ported in  New  York. 
The  bug  most  prevalent 
there  is  called  the  False 
Tarnish e'd  Plant  bug 
(Lygus  invitus  Say). 
Injury  by  the  tarnished 
plant-bugs  to  peach  has 
been  blamed  for  a  disease 
known  as  peach  stop- 
back.  Both  nymphs  and 
adults  injure  the  plants 
by  sucking  out  the  juices, 
X  »  f  n  and   on  many  plants  a 

Fig.  506.— The  tarnished  plant-bug  {Lygus  small  black  spot  appears 
vratensis  Linn.)  a  b,  c,  d,  four  stages  of  ^^ere  the  insect  has  been 
nymphs;  e,  adult  bug — all  about  four  times  ... 

natural  size.     (After  Forbes  and  Chittenden,  feedmg,  which   causes    a 

U.  S.  Dept.  Agr.)  deformation  of  the  stem 

or  leaf,  as  in  the  "buttoning"  of  strawberries,  or  tends  to  "bhght" 

the  terminal  as  in   the   case   of   dahhas,   potatoes,  and    similar 

crops. 

The  adult  is  nearly  one-quarter  inch  long,  of  a  brassy-brown 
color,  marked  with  black  and  yellow,  and  the  thorax  with  red. 
The  color  and  markings  are  quite  variable.  The  nymphs  feed 
upon  the  same  plants  as  the  adults  and  pass  through  four  stages, 
shown  in  Fig.  506.  The  first  stage  is  only  one-twentieth  inch 
long  and  yellowish  or  yellowish-green.  The  second  stage  is 
about  twice  as  large,  and  similarly  colored,  except  that  there  are 
two  pairs  of  dark  spots  on  the  thorax  and  one  on  the  middle  of  the 
third  abdominal  segment,  which  grow  more  distinct  in  the  last  two 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR  573 

stages.     With  the  third  stage  the  small  wing  pads  become  visible 
and  in  the  fourth  stage  they  extend  halfway  down  the  abdomen. 

Life  History. — The  adults  hibernate  over  winter  under  any 
shelter  available,  such  as  the  trash  on  affected  fields,  under 
leaves,  boards,  stones,  etc.,  and  emerge  in  early  spring.  The 
eggs  are  laid  in  Missouri  in  April.  But  little  is  known  of  the 
places  of  oviposition,  except  that  Taylor  *  has  shown  that  some- 
times apples  are  severely  dimpled  by  the  egg  punctures.  It  is 
evident,  therefore,  that  the  eggs  are  inserted  in  the  stems  or 
leaves  of  the  food-plants.  The  pale  yellow  egg  is  about  one- 
thirtieth  inch  long,  oval,  elongate,  and  flared  at  the  outer  end,  so 
as  to  be  somewhat  bottle-shaped.  The  first  generation  becomes 
full  grown  in  about  a  month,  after  which  all  stages  may  be  found 
feeding  together  until  September  or  October.  In  southern 
Missouri  Professor  Stedman  states  that  there  are  three  generations 
while  in  northern  Missouri  only  two,  but  the  exact  number  has 
not  been  carefully  determined. 

Control. — This  is  is  an  exceedingly  difficult  insect  to  control, 
owing  to  the  large  number  of  food-plants  and  the  fact  that  the 
adult  takes  wing  and  flies  off  quickly  upon  the  least  disturbance. 
As  it  sucks  its  food,  arsenical  insecticides  are  of  course  useless, 
and  some  contact  insecticide  must  be  used  with  which  the  insect 
may  be  hit.  The  nymphs  may  be  sprayed  at  any  time,  but  to 
hit  the  adult  bugs  they  must  be  sprayed  in  early  morning,  while 
still  sluggish.  Spraying  will  be  profitable  where  the  nymphs 
are  abundant,  but  it  is  doubtful  whether  it  will  be  found  a  satis- 
factory means  of  combating  the  adults.  Ten  per  cent  kerosene 
emulsion  and  tobacco  extracts  have  been  used  successfully. 
Where  they  are  abundant  the  adults  may  be  collected  in  consider- 
able numbers  by  sweeping  the  foliage  in  early  morning  with  a 
strong  insect  net  and  then  dropping  them  into  kerosene.  Clean 
culture,  including  the  destruction  of  all  weeds,  and  such  vegeta- 
tion or  trash  as  may  furnish  hibernating  quarters,  is  important, 
as  it  is  observed  that  injury  is  always  worse  where  weeds  have 
been  allowed  to  multiply  and  the  ground  has  been  covered  with 
weeds  and  trash. 

*  See  E.  P.  Taylor,  Journal  of  Economic  Entomology,  Vol.  I,  p.  370. 


574         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCAHRD 

Haseman  (1.  c.)  states  that  insecticides  have  been  of  httle 
value  in  the  control  of  the  insect  in  nurseries  and  recommends 
that  injury  be  prevented  by  destruction  of  the  weeds  which 
harbor  it,  particularly  members  of  the  Compositoe  of  which  the 
"Mare's  tail"  (Erigeron  canadensis)  is  said  to  be  the  most 
important. 


CHAPTER  XXVI. 
INSECTS  INJURIOUS  TO  THE  PEACH,  PLUM  AND  CHERRY  * 

The  Peach-tree  Borer  f 

Wherever  peaches  are  grown  they  are  subject  to  the  attacks 
of  the  ever-present  borers,  and  if  neglected  will  soon  succumb 
to  their  injury.  East  of  the  Rocky  Mountains  the  common  peach- 
tree  borer  has  been  known  since  the  earliest  settlements,  and  it 
also  occurs  in  Colorado  and  Oregon.  It  is  a  native  insect  which 
probably  lived  on  wild  cherry  and  wild  plum,  and  is  known  to 
attack  plum,  prune,  apricot  and  nectarine,  though  chiefly  a 
peach  pest.  On  the  Pacific  Coast  a  nearly  related  species,  the 
California  peach-tree  borer, |  does  similar  injury  and  has  very 
similar  habits.  The  lesser  peach-tree  borer  §  is  commonly  asso- 
ciated with  the  more  common  borer  and  has  done  considerable 
injury  in  western  New  York,  Maryland,  Virginia  and  Georgia. 
It  occurs  throughout  the  country  and  is  doubtless  commonly 
confused  with  the  larger  and  more  common  species.  Although 
it  is  quite  different  in  its  life  history  and  habits,  the  injury  is 
very  similar,  and  as  it  must  be  controlled  by  the  same  methods 
it  need  not  be  separately  considered. 

The  presence  of  the  borers  may  be  detected  by  the  mass  of 
gummy,  gelatinous  material,  more  or  less  mixed  with  soil,  which 
exudes  from  the  crowns  of  trees  injured  by  them.  The  injury 
is  done  by  the  larvae  feeding  on  the  soft  inner  bark  of  the  crown 
of  the  root,  the  adjacent  roots  and  the  base  of  the  trunk.  Often 
the  larvae  will  completely  girdle  a  tree  and  where  a  tree  is  infested 

*  See  J.  B.  Smith,  BuUetin  235,  N.  J.  Agr.  Exp.  Sta. 

t  Sanninoidea  exitiosa  Say.  Family  SesiidcB.  See  Quaintance,  Yearbook 
U.  S.  Dept.  Agr.,  1905,  p.  330;  M.  V.  Slingerland,  BuUetin  176,  CorneU  Univ. 
Agr.  Exp.  Sta.;  H.  N.  Starnes,  Bulletin  73,  Geo.  Agr.  Exp.  Sta. 

I  Sanninoidea  opalescens  Hy.  Ed.  See  C.  W.  Woodworth,  BuUetin  143, 
Cal.  Agr.  Exp.  Sta. 

§  Synanthedon  pictipes  G.  &  R.  See  A.  A.  Girault,  Bulletin  68,  Part  IV, 
Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  and  J.  L.  Iving,  BuUetin  307,  Ohio 
Agr.  Expt.  Station. 

575 


576 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


by  several  borers,  the  foliage  turns  yellow  and  if  not  treated  will 
soon  die.  Such  a  tree  is  much  more  susceptible  to  the  attacks 
of  bark  beetles  and  diseases.  Probably  as  many  peach  trees 
are  lost  from  the  work  of  borers  as  from  any  other  one  pest,  with 
the  possible  exception  of  the  San  Jos^  scale. 

The  adults  are  clear-winged  moths  which  fly  during  the  day 
and  might  be  readily  mistaken  for  wasps.  The  females  are  a 
deep  steel-blue  with  a  broad  orange  band  across  the  abdomen. 
The  fore-wings  are  opaque,  covered  by  the  bluish  scales,  and 


i.. 


Fig.  507. — Peach  borer  moths  (Sanninoidea  exitiosa  Say) — natural  size. 
The  upper  one  and  the  one  at  right  are  females,  the  other  two  males. 
(After  Slingerland.) 

expand  about  1^  inches,  while  the  hind-wings  are  transparent 
except  the  dark  margin.  The  males  are  smaller,  with  the  wings 
clear  except  the  margins  and  a  line  across  the  fore-wings,  and 
the  abdomen  is  marked  with  three  or  four  narrow  yellow  stripes. 
Life  History. — The  moths  emerge  in  New  York  and  New  Jersey 
from  the  middle  of  July  to  the  latter  part  of  August,  at  Wash- 
ington, D.  C,  from  the  middle  of  June  until  mid-September, 
the  majority  emerging  in  late  July,  while  in  Georgia  the  majority 
emerge  in  late  August  and  early  September.    As  there  is  but  one 


INSECTS  INJURIOUS  TO  PEACH,  PLUM  AND  CHERRY       577 


generation  a  year,  the  time  of  emergence  in  these  different  lati- 
tudes is  decidedly  anomalous  when  compared  with  the  hfe 
histories  of  other  insects.  The  females  soon  lay  their  eggs,  pre- 
ferring to  place  them  on  the  base  of  the  trunk,  but  often  placing 
them  higher,  or  even  on  weeds  or  trash,  or  on  the  soil.  A 
single  female  may  lay  from  200  to  800  eggs.  The  eggs  are 
about  one-fiftieth  inch  long,  and 
slightly  over  half  as  wide,  truncate 
at  one  end,  and  a  light  chestnut-brown 
or  reddish-brown  in  color,  not  easily 
seen  on  the  bark  of  the  tree.  They 
hatch  in  about  ten  da.ys  and  the 
young  larvse  at  once  seek  out  small 
cracks  in  the  bark  through  which  they 
enter  the  soft  bark  of  the  tree.  Their 
presence  may  be  easily  detected  by 
the  powdery,  brownish  rass  which  they 
throw  out  of  their  burrows.  The  young 
larvae  grow  rapidly  and  continue  feed- 
ing until  forced  into  hibernation  by 
cold  weather,  and  in  the  South  doubt- 
less feed  during  warm  days  in  the 
winter.  Feeding  is  resumed  in  the 
spring,  the   larvse  boring  through   the 

lower  layers  of  the  bark  and  causing  ^^^-   ^.^  ^  ~  ■^^^l  °K  ^^^ 

°       peach  borer:  natural  size 
masses    of    gum   to   exude  as   already 


at  n;  an  egg  greatly  en- 
larged at  I;  and  end  of 
egg  greatly  magnified, 
showing  micropj-le  at  m. 
(After  Slingerland.) 


described.  Larvae  of  almost  all  sizes 
may  usually  be  found  in  late  spring,  and 
the  resulting  moths  appear  irregularly 
over  a  period  of  two  to  three  months.  The  full-grown  borer  is  a  light 
yellowish  larva  about  1  inch  long,  with  a  brown  head  and  thoracic 
legs,  and  five  pairs  of  prolegs  on  the  abdomen.  The  body  is 
sparsely  clothed  with  brownish  hairs  which  arise  from  small, 
smooth  tubercles.  The  grown  larva  constructs  a  cocoon  at  or 
near  the  surface  of  the  ground,  usually  on  the  trunk  near  the 
burrow,  but  often  on  the  soil,  which  is  composed  of  particles 
of  excrement  and  bark,  bound  together  with  gum  and  a  thin 
lining  of  silk.  In  this  it  transforms  to  a  brown  pupa  from  which 
the  moth  emerges  in  about  three  weeks. 


578         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Control. — One  of  the  best  means  of  preventing  injury  and 
making  the  removal  of  the  borers  easier  is  to  mound  the  soil 
around  the  trunk  as  high  as  possible,  just  before  the  moths  emerge 
in  the  summer.  This  forces  them  to  lay  their  eggs  high  up  on  the 
trunk,  where  the  little  borers  may  later  be  readily  found.  In  some 
way  this  mounding  seems  to  prevent  the  establishment  of  the 
young  larvae,  as  several  experimenters  have  found  that  from  half 
to  three-fourths  of  the  borers  are  kept  out  of  the  trees  in  this 
way.  In  the  early  fall  the  earth  should  be  leveled  down  to  facil- 
itate finding  the  little  larvae.  Oviposition  on  the  lower  trunk 
may  also  be  prevented  by  wrapping  the  trunk  with  building 
paper,  or  any  heavy  paper,  which  should  extend  well  into  the 
soil  below  and  be  tied  tightly  just  below  the  crotch  at  the  top. 


Fig.  509. — ^The  peach  borer  larva,  natural  size  and  enlarged.     (After 
Slingerland.) 

Such  wrapping  may  be  used  to  advantage  with  the  mounding  up  of 
the  earth  and  thus  largely  prevent  oviposition.  The  wrappers 
should  be  applied  before  the  moths  appear  and  be  removed  in  the 
early  fall.  Various  washes  composed  of  soaps,  lime,  glue,  cement, 
carbolic  acid,  and  various  other  ingredients  have  been  commonly 
recommended  and  widely  used  for  preventing  the  laying  of  the 
eggs  and  the  entrance  of  the  young  larvae,  but  careful  tests  have 
failed  to  show  their  value.  Doubtless  this  is  due  to  the  roughness 
of  the  bark  of  the  peach,  over  which  it  is  difficult  to  make  a  com- 
plete coating,  and  the  fittle  larvae  will  enter  through  the  smallest 


INSECTS  INJURIOUS  TO  PEACH,  PLUM  AND  CHERRY      579 


crevice.  Some  wash  which  would  penetrate  the  burrows  of  the 
young  larvae  and  destroy  them,  as  does  the  avenarius  carboUneum 
with  the  bark  beetles,  would  seem  to  be  the  most  promising  line 
of  treatment,  and  some  of  the  washes  which  have  been  extensively 
used  by  practical  growers  should  be  critically  tested  on  a  com- 
mercial scale. 

Preliminary  experiments  in  West  Virginia  have  given  excellent 
results  in  the  control  of  the  borers  by  the  application  of  soluble 
oils  of  the  commercial  brands, 
at  dilutions  of  from  one  to 
twelve  to  one  to  nine.  The 
soil  is  scraped  away  from  the 
base  of  the  tree,  the  crown  and 
lower  part  of  the  trunk 
thoroughly  drenched  with  the 
oil,  applied  with  a  sprayer,  and 
the  soil  drawn  back  into  place 
about  the  tree. 

Mechanical  protectors  have 
generally  proven  to  be  of  little 
value  and  in  common  orchard 
practice  the  growers  still  de- 
pend very  largely  on  the  old 
fashioned  method  of  "worm- 
ing," that  is,  removing  the 
borers  from  the  trees  by  hand. 
This  may  be  done  in  the 
spring  or  in  the  fall.  Profes- 
sor Starnes  recommends  that, 
in  Georgia,  the  work  be  done 
in  the  fall  since  many  of  the 
small  borers  are  then  in  the 
surface  bark  and  in  masses  of 


Fig.  510.  — ■  Work  of  a  single  peach 
borer,  natural  size:  w,  b,  burrow  of 
borer;  ^,  gummy  mass;  p,  pupa  project- 
ing from  cocoon.     (After  Slingerland.) 


exuded  gum  and  may  be  easily  destroyed  while  in  the  spring  they 
are  found  in  better  protected  situations  under  the  bark.  In  the 
North  fall  worming  seems  to  be  less  satisfactory.  Tools  for  worm- 
ing consist  of  a  stout  knife  and  a  piece  of  steel  wire,  sharpened  at 
one  2nd.  Special  knives  with  curved  blades  are  sometimes  prefer- 
red. Some  use  the  ordinary  pruning  knife  and  some  prefer  a 
blade  similar  to  that  of  the  blacksmith's  hook-knife. 


580         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Peach  Twig-borer  * 

On  the  Pacific  Coast  the  Peach  Twig-borer,  often  known  there 
as  the  peach  worm,  is  one  of  the  most  serious  pests  of  the  peach. 
In  the  Eastern  States  it  has  been  injurious  in  Delaware,  Virginia 
and  Maryland,  but  only  occasionally.  Probably  the  insect  occurs 
throughout  the  country  wherever  the  peach  is  grown,  as  it  is 
an  old  European  insect  which  was  first  noticed  in  the  United 
States  in  1860.  On  the  Pacific  Coast  the  over-wintering  larvae 
bore  into  the  tender  shoots  in  early  spring  and  during  the  summer 

bore  into  the  fruit,  particularly 
the  later  varieties.  Prune, 
nectarine,  apricot,  almond, 
and  pear  are  also  injured. 

The  adult  moth  is  a  dark- 
gray  color,  with  fore-wings  ex- 
panding about  one-half  inch 
and  marked  with  darker  spots. 
The  full  grown  larva  is  about 
one-half  inch  long,  of  a  dull 
reddish-brown  color  with  dark 
brown  or  blackish  head. 

Life  History. — "The  insect 
passes  the  winter  as  a  very 
small  larva  in  silken-lined  cells 
Fig.    511. — The     peach     twig-borer  or    burrows    in    the    spongy 

(Anarsia  ZmeaJeZZa):  adult  moth  with  tissue    of    the    bark    at     the 
wings     spread     and     folded — ^much 

enlarged.      (After     Marlatt,     U.     S.  Crotches  of  the  limbs.      Their 
Dept.  Agr.)  presence  is  indicated  by  small 

mounds  of  comminuted  bark,  as  shown  in  Fig.  512,  at  a  and  6. 
Early  in  the  spring,  as  the  foliage  is  putting  out,  the  larvae  begin 
to  leave  their  burrows  and  attack  the  tender  shoots,  boring  into 
and  down  the  pith,  the  galleries  ranging  from  about  one-third  inch 
to  1|  inches  in  length.  The  shoot  thus  injured  soon  wilts  and 
dies,  as  shown  in  Fig.  513,  at  a.  Many  shoots  may  be  attacked  by 
a  single  larva,  which  is  thus  capable  of  doing  considerable  harm. 
There  are  two  or  three  generations  of  larvae  during  the  summer  in 

*  Anarsia  lineatella  Zell.  Family  Gelechiidoe.  See  W.  T.  Clarke,  Bulletin 
144,  Cal.  Agr.  Exp.  Sta.;  C.  L.  Marlatt,  Bulletin  10,  n.  s.,  Div.  Ent.,  U.  S. 
Dept.  Agr.;  A.  L.  Quaintance,  Yearbook  U.  S.  Dept.  Agr.,  1905,  p.  344. 


INSECTS  INJURIOUS  TO  PEACH,  PLUM  AND  CHERRY      581 


Fig.  512. — Peach  twig-borer  in  winter 
quarters:  o,  twig,  showing  in  crotch 
minute  masses  of  chewed  bark  above 
larval  chamber;  b,  same,  much  en- 
larged; c,  larval  cell  enlarged;  and 
d,  larva  very  greatly  enlarged.  (After 
Marlatt,  U.  S.  Dept.  Agr.) 


the  West,  those  of  the  second  and  third  attacking  the  fruit,  the 
later  varieties  being  the  worst  injured.  According  to  Professor  C. 
V.  Piper,  the  larva  enters  the  peach  at  the  stem  end,  usually  bor- 
ing into  the  pit,  the  seed  of  which 
it  seems  to  prefer,  usually  caus- 
ing the  stone  to  split  as  the  fruit 
ripens;  or  simply  the  flesh  may 
be  tunnelled,  depending  on 
whether  or  not  the  stone  is  hard 
when  the  fruit  is  attacked.  In 
Cahfornia,  according  to  Clarke, 
the  larva  usually  enters  the  fruit 
along  the  suture  at  the  stem 
end,  and  excavates  a  chamber 
beneath  the  skin,  which  black- 
ens and  shrivels  somewhat,  af- 
fording entrance  to  organisms 
of  decay.  In  the  ripe  fruit  the 
larvae  frequently  make  their  way  to  and  around  the  stone,  which,  if 
spUt,  may  be  entered  and  the  seed  feed  upon.    .    .    .     Early  in  the 

fall,  about  September  1,  in 
Cahfornia,  the  very  young 
larvae  from  eggs  of  the  last 
generation  of  moths  construct 
their  hibernation  cells  in  the 
soft  tissue  of  the  crotches  of 
limbs,  where  they  remain  un- 
til the  following  spring,  thus 
spending  some  six  months  in 
this  condition." — Quaintance. 
Control. — By  spraying  dur- 
ing the  winter,  or  preferably 
after  the  buds  have  swollen 
in  the  spring  with  kerosene 
or  distillate-oil  emulsion,  the 
oil  is  absorbed  by  the  cast- 
mgs  at  the  mouth  of  the  burrows  of  the  hibernating  larvae,  and 
thus  penetrates  the  burrows  and  kills  the  larvae.     Lime-sulfur  wash 


FiQ  513. — ^The  peach  twig-borer:  a,  new 
shoot  of  peach  withering  from  attacks 
ot  larvse;  b,  larva  enlarged;  c,  pupa, 
enlarged.  (After  Marlatt,  U.  S.  Dept. 
Agr.) 


582       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

applied  from  the  time  the  buds  commence  to  swell  until  the 
first  blossoms,  has  also  been  widely  and  successfully  used. 
The  wash  should  be  applied  as  late  as  possible  before  blossoming. 
Recently  Mr.  E.  P.  Taylor  has  shown  *  that  in  western  Colorado 
the  larvse  are  very  readily  killed  by  arsenate  of  lead,  3  to  5  pounds 
per  barrel,  applied  just  as  the  buds  are  beginning  to  open.  The 
arsenate  of  lead  must  contain  no  soluble  arsenic,  or  it  may  burn  the 
foliage.  This  treatment  is  given  at  the  same  season  as  the  lime- 
sulfur  wash  and  is  much  easier  to  prepare  and  apply. 

The  Peach-tree  Bark-beetle  f 

The  peach-tree  bark-beetle  is  very  similar  in  both  appearance 
and  habits  to  the  fruit-tree  bark-beetle,  and  may  be  readily 
confused  with  it.  It  is  a  native  insect  which  attacks  only  peach, 
cherry  and  wild  cherry,  and  so  far  has  been  injurious  only  in 
western  New  York,  northern  Ohio,  and  the  Niagara  district 
of  Ontario,  though  it  occurs  from  New  Hampshire  to  North 
Carolina  and  west  to  Michigan. 

"When  the  beetles  are  present  in  large  numbers  their  injury 

to  the  tree  is  quickly  brought  to  the  attention  of  the  orchardist 

by  the  large  amount  of  sap  exuding  from  the  trees  through  the 

many  small  borings  made  both  in  the  trunk  and  limbs  of  the 

tree.  .  .  .  The  adults  or  beetles  produce  the  primary  injury  to 

healthy  trees,  the  work  of  the  larvse  being  secondary.     The  healthy 

trees,  by  repeated  attacks  of  the  adults,  are  reduced  to  a  condition 

favorable  to  the  formation  of  egg-burrows.     When  the  beetles 

are  ready  to  hibernate  in  the  fall  they  fly  to  the  healthy  trees  and 

form  their  hibernation  cells.     These  latter  are  injurious  to  the 

trees,  for  through  each  cell  there  will  be  a  tiny  flow  of  sap  during 

the  following  season."     When  the  beetles  emerge  in  the  spring 

they  bore  into  the  bark  of  healthy  trees  and  later  leave  them  to 

form  egg  burrows  in  sickly  trees.     From  these  numerous  burrows 

the  sap  issues  in  large  quantities  and  in  many  cases  forms  large 

gummy  masses  around  the  trees.     After  three  or  four  years  of 

such  injury  the  tree  is  so  weakened  that  the  beetles  form  their 

egg  burrows  beneath  the  bark  and  the   larvse  soon  finish  its 

*  E.  P.  Taylor,  Bulletin  119,  Colo.  Agr.  Exp.  Sta.,  p.  8. 
t  PhlcBotribus  liminaris  Harris.     Family  Scolytidce.     See  H.    F.  WUson, 
Bulletin  68,  Part  IX,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  PEACH,  PLUM  AND  CHERRY       583 

destruction.  There  are  two  generations  a  year,  the  summer  brood 
appearing  in  the  latter  half  of  August  and  the  other  hibernating 
over  winter. 

Control. — The  same  methods  are  advised  as  for  the  fruit-tree 
bark-beetle,  which  see. 


The  Peach  Lecanium  * 

The  presence  of  the  "terrapin  scale,"  as  this  species  is  often 
called,  is  usually  indicated  by  the  sooty  appearance  of  the  branches 
and  foliage  of  affected  trees.  This  is  due  to  the  fact  that  the 
scales  excrete  considerable  honey-dew,  which  covers  the  bark  and 


Fig.  514. — ^The  peach  lecanium  or  terrapin  scale  (Eulecanium  nigrofasciatum 
Pergande):  adults  at  left,  natural  size  and  much  enlarged;  young  at 
right,  and  unfertQized  female  at  center — much  enlarged.  (After  Howard, 
U.  S.  Dept.  Agr.) 

leaves,  and  on  which  a  sooty  fungus  propagates.  It  is  a  common 
species  throughout  the  eastern  United  States  and  also  attacks 
the  apple,  maple,  sycamore,  linden  and  birch,  but  is  most  injurious 
to  peach  and  plum.  The  hibernating,  partly  grown,  female  scale 
found  on  the  bark  in  winter,  is  about  one-twelfth  inch  long, 
hemispherical,  and  of  a  reddish  color  mottled  with  radiating 
streaks   of   black,    particularly   about   the   margin.     Sometimes 

*  Euclecanium  nigrofasciatum  Pergande.  Family  Coccidoe.  See  J.  G. 
Sanders,  Circular  88,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. ;  A.  L.  Quain- 
tance,  Yearbook  U.  S.  Dept.  Agr.,  1905,  p.  340;  T.  B.  Symons  and  E.  N.  Cory, 
Bulletin  149,  Md.  Agr.  Exp.  Sta.,  and  F.  L.  Simanton,  Bulletin  351,  U.S. 
Dept.  Agr. 


584       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


these  streaks  coalesce  and  form  a  dark  band  around  the  center, 

while  other  individuals  are  occasionally  entirely  red  or  black. 

Frequently  trees  become  badly  encrusted  with  these  scales,  but 

rarely  are  they  killed  by  them.     The  fruit  on  badly  infested 

trees  is,  however, 
poorly  developed,  in- 
sipid, and  covered 
with  the  sooty  fungus 
so  as  to  be  almost 
unsaleable,  and  the 
trees  are  stunted  and 
rendered  more  hable 
to  the  attack  of  other 
insects. 

Life  History . — 
There  is  but  one  gen- 
eration a  year.  In 
the  winter  they  are 
mostly  nearly  grown 
female  scales.  These 
mature  early  in  the 
spring  and  deposit 
their  eggs  in  a  mass 
beneath  the  body, 
which  forms  the  hard 
scale  above  them.  In 
Missouri  the  eggs 
hatch  about  June 
10th,  and  continue  to 
hatch  for  a  month. 
The  male  scales  are 
much  smaller  than 
enlarged.  (After  the  females,  elongate, 
sHghtly  convex,  and 
greenish-white  in  color.  Late  in  July  the  winged  males  appear 
and  hve  about  a  week.  The  young  female  scales  continue  growth 
during  the  summer  and  hibernate  when  about  two-thirds  grown. 
Control. — Lime  sulphia*  seems  to  be  ineffective  against  this 
insect  but  orchards  which  are  sprayed  year  after  year  with  it 


Fig.  515. — ^The  Peach  Lecanium— 
Simanton.) 


INSECTS  INJURIOUS  TO  PEACH,  PLUM  AND  CHERRY     585 

suffer  less  than  unsprayed  ones.  The  best  treatment  for  general 
use  is  miscible  oil  spraying.  The  oils  to  be  used  at  about  one  to 
16  or  18  and  appUed  in  the  spring  after  the  buds  swell  but  before 
they  open.     Two  treatmenis  in  successive  years  must  be  given  to 


Fig.  516. — Distribution  in  the  United  States  of  the  terrapin  scale  (Eulecan- 
ium  nigrofasciatum) .     (After  Simanton,  I.e.) 

get  the  full  benefit  and  it  is  better,  in  infested  regions,  to  make  it 
an  annual  treatment. 

The  Black  Peach-aphis  * 

The  black  peach-aphis  is  a  native  species  which  has  been  most 
injurious  in  the  Middle  Atlantic  States,  but  has  become  widely 
distributed  on  nursery  trees.  It  attacks  the  roots,  tender  shoots 
and  fohage  of  the  peach.  When  occurring  on  the  roots,  trees  are 
often  seriously  injured  before  its  presence  is  suspected.  Young 
trees  are  particularly  affected,  the  injured  trees  having  a  yellowish 
sickly  foHage.  Usually,  however,  the  presence  of  the  aphids 
on  the  young  shoots  and  leaves  will  be  an  indication  of  its  inhab- 
iting the  roots  also.  In  the  spring  and  early  summer  the  aphids 
cluster  on  the  tender  shoots  at  the  crotch  of  the  tree  and  low 
down  on  the  limbs  and  soon  form  a  disgusting  black  mass  over 
the  young  leaves,  which  are  tightly  curled  up  from  the  injury. 


586       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


On  young  trees  in  the  nursery  and  on  young  orchard  trees,  this 
injury  to  the  foUage  is  sometimes  so  severe  as  to  kill  or  severely 
check  the  growth. 

Both  winged  and  wingless  aphids  are  found  on  the  foliage, 
but  only  the  wingless  forms  occur  on  the  roots.  Both  forms  are 
about  one-twelfth  inch  long  and  shining  deep  brown  or  black 
in  color  when  mature.  The  partly  grown  aphids,  which  form 
the  larger  part  of  most  colonies,  are  reddish-yellow  or  amber 
colored. 

Life  History. — The  wingless  aphids  feed  and  reproduce  upon 
the  roots  throughout  the  year,  all  being  females  and  giving  birth 


Fig.  517. — ^The  black  peach-aphis  (Aphis  persicoe-niger  Er.  Sm.):  winged 
viviparous  female;  young  female,  first  instar;  apterous  viviparous  female — 
much  enlarged.     (After  Gillette  and  Taylor.) 

to  live  young  after  the  manner  of  the  aphids.     In  the  spring 

some  of  them  migrate  to  the  young  foliage,  often  appearing  on  the 

tender  twigs  before  the  buds  open.     They  multiply  rapidly,  and 

as  a  result  of  the  hundreds  of  Httle  beaks  sucking  out  the  juices 

the  shoot  soon  withers,  which  causes  the  young  to  develop  into 

winged   aphids   which   migrate   to   other   trees.     Honey-dew   is 

excreted  very  freely  by  the  aphids,  which  are  therefore  attended 

by  numerous  ants  which  doubtless  aid  in  their  transportation 

from  tree  to  tree  and  from  the  roots  to  the  leaves  and  back. 

"During  summer  the  aphids  for  the  most  part  are  to  be  found 

*  Aphis  persicce-niger  Er.  Sm.  Family  Aphididoe.  See  C.  P.  Gillette, 
Bulletin  133,  Colo.  Agr.  Exp.  Sta.,  p.  37;  A.  L.  Quaintance,  Journal  of  Eco- 
nomic Entomology,  Vol.  I,  p.  308,  Yearbook  U.  S.  Dept.  Agr.,  1905,  p.  342. 


INSECTS  INJURIOUS  TO  PEACH,  PLUM  AND  CHERRY    587 

on  the  roots,  though  a  few  may  be  found  on  the  foliage  and  the 
shoots  in  badly  infested  orchards  at  almost  any  time  during  the 
growing  season  .  .  .  Light  sandy  soils  are  worst  infested,  though 
they  have  been  found  in  abundance  on  stiff  clay  soils.  "  (Quain- 
tance.  I.e.)- 

Control. — The  roots  of  young  trees  suspected  of  being  affected 
should  be  carefully  examined  and  if  aphids  are  found  they  should 
be  dipped  in  strong  tobacco  water.  Nurserymen  prevent  injury 
by  making  liberal  apphcations  of  tobacco  dust  in  the  trench  and 
along  the  rows.  Tobacco  dust  may  also  be  used  against  the 
aphids  on  the  roots  of  orchard  trees  by  removing  the  surface 
soil  and  applying  a  liberal  dressing  of  the  dust,  which  will  be 
leached  down  on  to  the  roots  by  the  rains.  It  should  be  appUed 
over  the  smaller  roots.  The  treatment  for  the  root  forms  has 
not  been  sufficiently  studied  to  warrant  any  conclusions  as  to 
satisfactory  methods,  but  the  same  as  advised  for  the  woolly  apple- 
aphis  (p.  518)  are  suggested.  When  the  aphids  appear  on  the 
young  shoots  in  the  spring  they  may  be  readily  controlled  if  the 
trees  are  observed  for  their  appearance,  for  they  are  very  grega- 
rious, clustering  on  one  shoot  until  it  is  well  covered  before  spread- 
ing to  the  rest  of  a  tree,  and  becoming  abundant  on  it  before 
spreading  to  others.  Often  the  small  infested  shoots  may  simply 
be  broken  off  and  destroyed.  The  aphids  may  be  killed  by 
spraying  them  with  tobacco  extract. 

The  Green  Peach-aphis  * 

This  aphid  is  a  European  species  which  has  long  been  known 
as  a  pest  of  peach  foHage  in  this  country,  where  it  has  become 
widely  distributed.  Considerable  interest  attaches  to  the  species, 
as  it  furnishes  a  striking  example  of  the  summer  migration  of 
aphids  to  different  food-plants,  and  a  consequent  difference 
in  appearance  in  form  and  color.  During  the  summer  this  species 
feeds  upon  various  vegetables  and  succulent  plants,  and  is  so 
different  in  color  and  form  that  it  has  been  well  known  not  only 
as  a  separate  species,  but  as  belonging  to  a  distinct  genus.  Con- 
cerning its  injury  to  the  peach,  E.  P.  Taylor  states:  "The 
peach-growers  of  Western  Colorado  have  suffered  loss  from  it, 
from  its  heavy  infestation  of  the  leaves  of  the  trees  in  the  spring. 


588      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

causing  them  to  curl  and  drop  prematurely  to  the  ground,  and 
from  the  withering  and  subsequent  dropping  of  the  buds  and 
forming  peaches  also  infested  by  the  aphids  at  this  time. "  Similar 
injury  has  been  reported  from  Missouri,  and  doubtless  occurs 
occasionally  in  other  sections. 

Life  History. — The  winter  is  usually  passed  in  the  egg  stage 
on  the  peach,  plum,  apricot,  nectarine,  cherry  or  other  trees, 
though  the  wingless  females  sometimes  persist  on  the  summer 
food-plants  where  there  is  sufficient  protection  to  enable  them  to 
endure  the  cold  of  winter,  as  in  cabbage  pits,  or  in  the  South.  The 
small,  oval,  shining  black  eggs  are  deposited  in  the  axils  of  the 
buds  or  in  crevices  of  the  bark.  "The  eggs  hatch  very  early 
in  the  spring  so  that  the  young  stem-mothers  from  them  are 
often  almost  fully  grown  before  the  earliest  peach  or  plum  blos- 
soms open.  About  the  time  the  buds  begin  to  open  on  these 
trees,  the  stem-mothers  are  all  of  a  deep  pink  color  and  begin  to 
give  birth  to  living  young.  These  young  instead  of  being  pink 
like  their  mothers  are  pale  yellowish-green  throughout  their 
Mves,  and  usually  there  is  a  median  and  two  lateral  dark  green 
stripes  passing  over  the  abdomen.  Very  few  of  this  brood  attain 
wings.  The  third  generation  become  very  largely  winged  and 
begin  leaving  the  trees  upon  which  they  were  born  about  the  mid" 
die  of  May  in  the  peach-growing  sections  of  the  State  (Colorado). 
By  the  middle  of  June  these  lice  have  almost  completely  left  the 
trees  and  may  be  found  establishing  their  colonies  upon  various 
succulent  vegetables."  The  winged  females  which  migrate 
from  the  peach  are  about  one-twelfth  inch  long,  with  a  wing 
expanse  of  one-third  inch.  They  are  a  yellowish-green  color  with 
head,  antennae,  thoracic  lobes,  honey-tubes,  a  large  spot  on  the 
centre  of  the  abdomen,  and  small  lateral  spots  in  front  of  the 
honey-tubes  are  blackish.  The  wingless  females  during  the 
summer  are  pale  yellowish  and  lack  the  longitudinal  green  stripes 
on  the  abdomen.  According  to  Taylor's  observations  the 
spring  generations  on  peach  become  full  grown  in  about  two 
weeks  and  an  individual  aphid  lives  about  a  month.     In  the  fall 

*  Myzus  persicce.  Sulz.  Family  AphididcB.  (Syn. — Rhopalosiphum  dianthi 
Schr.).  See  Gillette  and  Taylor,  Bulletin  133,  Colo.  Agr.  Exp.  Sta.,  p.  32; 
C.  P.  Gillette,  Journal  of  Economic  Entomology,  Vol.  I,  p.  359;  E.  P.  Taylor, 
ihid.,  p.  83;  F.  H.  Chittenden,  Bulletin  2,  Va.  Truck  Exp.  Sta.,  p.  30. 


INSECTS  INJURIOUS  TO  PEACH,  PLUM  AND  CHERRY     589 

winged  females  return  to  the  peach  and  winter  host-plants,  and 
give  birth  to  young  which  develop  into  wingless  females  which 
lay  the  winter  eggs.  The  true  males  are  winged  and  migrate 
from  the  summer  food-plants. 

Control. — The  trees  affected  should  be  sprayed  about  a  week 


Fig.  518. — The  green  peach  Aphis  (Myzus  persicce  Siilz.) :  5,  adult  stem  mother; 
6,  young  of  stem  mother;  7,  apterous  viviparous  female  of  second  genera- 
tion; 8,  spring  migrant;  9,  fall  migrant;  10,  egg-laying  female;  11,  eggs — 
all  much  enlarged.     (After  Gillette  and  Taylor.) 

before  the  buds  open  with  tobacco  extract.  If  the  trees  are  sprayed 
with  lime-sulfur  for  the  twig-borer  just  before  blossoming,  it 
should  kill  most  of  the  aphids.  Tobacco  extract  may  be  used  on 
the  foUage  of  affected  plants  as  necessary. 


590        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Green  Soldier  Bug  * 

The  Green  Soldier  Bug  has  done  serious  injury  to  peaches 
in  Ohio  and  West  Virginia  as  well  as  other  localities  in  recent  years 
and  is  known  as  an  important  enemy  of  garden  crops,  particularly 
Lima  beans.  It "  stings  "  the  developing  pods  of  the  beans,  sucks 
the  sap  from  them  and  no  beans  develop. 

Its  injury  to  peaches  is  done  by  sucking  sap  from  the  develop- 
ing fruits  from  the  time  they  are  half-grown  until  they  ripen. 

The  adult  is  one  of  our  larger  green  stink-bugs  of  the  common- 
stink-bug  form  and  will  be  easily  recognized  from  its  name. 
The  nymphs  are  darker  in  color,  ranging  from  blackish  to  yellowish- 
green  with  black  markings,  depending  upon  the  stage.  The 
nymphs  are  more  likely  to  be  observed  doing  the  damage  than  are 
the  adults. 

This  species  is  very  similar  to  another  southern  form  called 
the  southern  green  plant-bugf,  which  injures  fruits  but  is  more 
important  as  a  pest  on  truck  crops. 

Control. — It  is  fortunate  that  this  insect  is  held  in  check  by 
climate  and  natural  enemies  since  there  are  no  artificial  control 
measures  available  as  yet.  Hand  picking,  or  jarring  into  cans 
of  kerosene,  might  pay  on  a  small  scale  in  gardens.  It  appears 
that  the  insect  may  be  expected  to  occur  in  injurious  numbers 
only  after  mild  winters  and  it  is  attacked  by  several  parasites  so 
its  occurrence  as  a  pest  is  only  occasional. 

The  Plum  Gouger  { 

This  is  a  native  beetle  which  breeds  upon  wild  plums  and  is 
most  injurious  to  native  varieties.  It  is  common  throughout 
the  Mississippi  Valley,  but  seems  to  be  most  injurious  westward 
and  occurs  in  Colorado.  The  work  of  the  beetles  might  be  easily 
mistaken  for  that  of  the  curculio  (p.  505).  The  adult  beetle  is 
readily  distinguished  from  the  curcuUo,  however,  by  lacking  the 
humps  on  the  wing-covers. 

*  Nezara  hilaris  Say.  See  R.  D.  Whitmarsh,  Bulletin  310,  Ohio  Expt. 
Station,  and  p.  236,  Chapter  XIII. 

t  Nezara  viridula  L.  See  T.  H.  Jones,  Bulletin  689,  U.  S.  Dept.  Agr.,  and 
J.  R.  Watson,  Bulletin  134,  Florida  Expt.  Sta.,  also  page  630,  Chapter  XXVII. 

t  Coccotorus  scutellaris  Lee.     Family  CurciilionidcB. 


INSECTS  INJURIOUS  TO  PEACH,  PLUM  AND  CHERRY     591 


It  is  about  one-quarter  inch  long,  with  a  snout  half  as  long, 
the  wing-covers  are  a  leaden-gray  color,  finely  spotted  with 
black  and  brown,  while  the 
thorax  and  head  are  marked 
with  ochreous  yellow. 

Life  History. — Like  the  cur- 
culio,  the  beetles  hibernate  over 
winter  and  appear  in  the  spring 
as  the  trees  blossom.  At  first 
they  puncture  the  calyx  and  feed 
on  the  ovary  of  the  flower,  com- 
pletely destroying  it  for  fruit  pro- 
duction, and  then  puncture  the 
growing  plums,  both  for  food 
and  for  egg-laying.  In  feeding 
on  the  plums  the  adults  gouge  out 
small  round  holes,  from  which  gum 
exudes.  Like  the  curcuHos,  they 
have  the  habit  of  feigning  death 
and  dropping  to  the  ground  when 
disturbed.  The  eggs  are  laid 
while  the  pit  of  the  plum  is  still 
soft.  The  female  beetle  drills  a  small  hole  which  is  larger  below, 
in  the  plum,  and  in  it  deposits  a  small  yellowish-white  egg, 
whose  outer  end  lies  flush  with  the  surface  of  the  plum.  As  soon 
as  the  larva  hatches  it  eats  its  way  into  the  pit,  feeding  upcai  the 
meat  of  the  seed  until  full  grown.  It  then  eats  a  hole  through 
the  outside  of  the  pit  so  that  the  adult  beetle  may  escape,  and 
then  transforms  to  a  pupa.  The  larva  is  very  similar  to  that  of 
the  curcuho,  but  is  a  milky  white  rather  than  a  glossy  white  and 
lacks  the  reddish  tinge  on  the  lower  surface.  Affected  plums  do 
not  drop  as  when  injured  by  the  curculio.  The  pupal  stage  is 
passed  in  the  pit  of  the  plum  and  the  adult  beetle  emerges  through 
the  hole  cut  for  it  by  the  larva.  The  beetles  emerge  a  Httle  before 
the  plums  ripen  and  often  practically  destroy  them,  as  fruit  badly 
punctured  becomes  gnarly  and  worthless.  The  beetles  feed  on  the 
plums  a  short  time  and  then  seek  hibernating  quarters  for  the  winter. 

Control. — Control  measures  have  not  been  thoroughly  tested, 
but  where  the  beetles  are  abundant  it  would  be  well  to  try  spray- 
ing with  arsenate  of  lead  as  advised  for  the  curcuho. 


Fig.  519. — The  plum  gouger  (Cocco- 
torus  scutellaris  Lee):  a,  plum 
stone  showing  exit  hole  of  larva; 
b,  adult;  c,  side  view  of  head  of 
beetle — enlarged.  (After  Riley 
and  Howard,  U.  S.  Dept.  Agr.) 


592      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Plum  Aphids 

Three  species  of  aphids  are  common  on  the  plum  foliage  in 
spring  and  fall,  and  often  do  serious  damage  by  curling  up  the 
foliage  in  the  spring  and  causing  it  to  drop  prematurely,  thus 
checking  the  growth  of  the  tree  and  preventing  proper  fruiting. 
The  life  histories  of  the  three  species  are  very  similar  in  that  the 
eggs  are  laid  upon  the  plum  in  the  fall,  upon  which  two  or  three 
generations  develop  in  the  spring,  but  in  early  summer  they 
migrate  to  other  food-plants,  from  which  they  return  to  the  plum 
in  the  fall.  The  life  history  is  much  the  same  as  that  of  the 
apple-aphis,  and  green  peach-aphis,  and  need  not  be  rehearsed 
in  detail. 

The  Mealy  Plum-louse  * 

This  is  a  light-green  species  which  is  covered  by  a  bluish- white 
mealy  powder.     It  has  a  long  narrow  body,  one-tenth  inch  long. 


Fig.  520. — The  mealy  plum  louse  (Hyalopterus  arundinis  Fab.):  a,  young 
nymph;  h,  last  stage  of  nymph  of  winged  form;  c,  winged  viviparous 
female — all  much  enlarged.     (After  Lowe.) 

marked  with  three  longitudinal  stripes  of  a  darker  green.     The 

honey-tubes  are  short,  thick,  and  slightly  constricted  at  the  base. 

The  winged  female  is  similar  in  coloration  except  that  the  abdomen 

bears  several  transverse  triangular  marks  of  darker  green.     In 

June  the  winged  females  migrate  to  certain  grasses  upon  which 

the  aphids  reproduce  during  the  summer,  though  small  colonies 

*  Hyalopterus  arundinis  Fab.  Family  Aphididce.  W.  D.  Hunter  in 
Bulletin  60,  Iowa  Agr.  Exp.  Sta.,  p.  92,  states  that  Aphis  prunifolice  Fitch 
is  probably  the  same  species.  Certainly  H.  arundinis  and  pruni,  Aphis 
pruni  and  prunifolioe,  seem  to  have  been  applied  to  the  same  species  in  the 
economic  literature  in  America.  See  Lowe,  V.  L.,  Bulletin  139,  N.  Y.  Agr. 
Exp.  Sta.,  p.  657,  and  W.  M.  Davidson,  Bulletin  774,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  PEACH,  PLUM  AND  CHERRY      593 

are  to  be  found  on  the  plum  throughout  the  summer.  In  the 
fall  they  return  to  the  plum,  where  the  winter  eggs  are  laid.  This 
species  is  known  to  occur  in  Germany,  England,  Austraha,  and 


Fig.  521. — Mealy  plum  aphides  clustered  on  leaf.     (After  Lowe.) 

New  Zealand,  and  seems  to  be  widely  distributed  over  the  United 
States.  It  occurs  here  on  plum  and  prune  and  in  Europe  is  said 
to  infest  grape,  peach,  apricot,  and  nectarine,  according  to  Lowe. 

The  Hop  Plant-louse  * 

This  species  is  best  known  as  a  pest  of  hops  during  the  summer 
and  rarely  does  very  serious  damage  to  the  plum,  though  often 
quite  abundant  on  it.  The  wingless  aphids  are  hght  green  or 
yellowish  green  without  any  noticeable  markings.  The  winged 
forms  have  the  same  body  color,  with  the  head,  thoracic  lobes, 
and  a  few  dashes  on  the  abdomen,  black.  The  species  may  be 
readily  distinguished  by  the  prominent  tubercle  which  projects 
from  the  head  on  the  inside  of  the  base  of  each  antenna,  and  a 
less  prominent  tubercle  on  the  basal  segment  of  each  antenna. 
According  to  the  studies  of  Dr.  C.  V.  Riley  and  his  assistants, 
the  third  generation  in  the  spring  migrates  from  the  plum  to 
hops  in  late  spring  and  in  fall  winged  viviparous  females  give 
birth  to  a  few  young  which  develop  into  egg-laying  females  which 

*  Phorodon  humuli  Schrank.  Family  Aphididoe.  See  C.  V.  Riley,  Report 
U.  S.  Dept.  Agr.,  1888,  p.  93;  W.  T.  Clarke,  Bulletin  160,  Cal.  Agr.  Exp.  Sta. 


594      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

mate  with  winged  males  which  have  developed  on  hops,  the 
winter  eggs  being  laid  on  the  plum  and  other  species  of  Prunus. 
In  Cahfornia,  Clarke  has  been  unable  to  find  any  evidence  of 
the  species  on  plum  or  other  vegetation  outside  of  the  hop  yards, 
where  he  finds  the  true  sexes  occuring  in  the  fall,  but  no  evidence 
of  eggs.  Hops  are  often  seriously  damaged  by  being  reduced  in 
size  and  weight  and  from  the  loss  in  aroma  due  to  the  presence 
of  the  aphids  in  them.  The  species  is  of  European  origin,  where 
it  is  a  well-known  enemy  of  hops,  and  has  become  widely  dis- 
tributed in  the  United  States  and  Canada. 

Control. — Where  it  oviposits  on  plum  it  may  be  best  con- 
trolled by  spraying  as  for  the  other  plum  aphids  in  the  spring. 
After  it  becomes  estabhshed  on  hops  it  may  be  controlled  by 
spraying  with  "Black-leaf  40." 

The  Rusty-brown  Plum-louse  * 

This  species  is  readily  distinguished  from  others  common  on 
plum  and  prune  by  the  dark  rusty-brown  color,  with  the  base 
of  the  antennae,  tibise,  and  tail  a  contrasting  white.  This  species 
has  become  a  very  serious  pest  to  plum  foliage  in  the  South  and 
Southwest,  and  we  have  observed  serious  injury  in  New  Hamp- 
shire, so  that  it  is  evidently  widely  distributed.  The  aphids 
collect  on  the  tender  young  twigs,  which  they  stunt  or  kill,  assemble 
on  the  under  sides  of  the  leaves,  which  become  corrugated  and 
curled  from  their  attack,  and  when  abundant  they  attack  the 
blossoms  and  their  stems  and  thus  prevent  the  setting  of  fruit. 
In  early  summer  the  winged  females  migrate  to  various  common 
grasses,  such  as  fox-tail,  red  top,  barnyard  grass,  crab  grass,  and 
others,  upon  which  they  breed  during  the  summer,  and  from  which 
the  winged  forms  return  to  plum  in  the  fall.  They  become 
darker  in  color  late  in  the  season  and  the  wingless,  egg-laying 
female  is  almost  black,  as  is  also  the  small  winged  male. 

Control. — The  treatment  advised  for  the  apple-aphis  (p.  537) 
will  be  effective  for  the  three  species  above,  while  on  the  plum, 
and  the  spraying  should  be  done  early  in  the  season  before  the 
aphids  have  become  numerous  and  curled  the  foliage. 

*  Aphis  setaricB  Thos.  Family  Aphididce.  See  Gillette  and  Taylor, 
Bulletin  133,  Colo.  Agr.  Exp.  Sta.,  p.  41;  C.  E.  Sanborn,  Bulletin  88,  Okla- 
homa Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  PEACH,  PLUM  AND  CHERRY     595 


The  Black  Cherry-louse  * 

This  species  has  long  been  known  as  a  cherry  pest  in  Europe 
and  during  the  last  fifty  years  has  become  generally  distributed 
over  the  eastern  United  States,  and  occurs  in  Colorado.  So  far 
as  known  the  cherry  is  the  only  food-plant.  Dr.  Weed  was  of 
the  opinion  that  the  aphids  left  the  cherry  during  late  July  and 
migrated  to  some  summer  food-plant  which  he  was  unable  to 
find,  but  observations  by  Gillette  and  Taylor  in  Colorado  would 
indicate  that  they  may  remain  on  the  cherry,  but  become  so 
reduced  in  numbers  by  their  natural  enemies  that  only  a  few 
survive  during  midsummer,  and  these  give  rise  to  larger  colonies 
in  late  summer  and  early  fall.  Both  the  winged  and  wmgless 
forms  are  deep  shining  black,  the  body  is  rather  broad  and  flat, 


/' V- 


Fig.  522. — ^The  black  cherry-aphis  (Myzus  cerasi  Fab,):  1,  apterous  vivip- 
arous female;  2,  winged  viviparous  female — enlarged.  (After  GUlette 
and  Taylor.) 

and  the  honey-tubes  are  unusually  long  and  are  cylindrical. 
Small  winged  males  and  wingless  females  occur  on  the  foliage  in 
the  fall  and  the  latter  lay  their  eggs  on  the  twigs  about  the  buds. 
Like  the  black  peach-aphis,  this  species  has  the  habit  of  accumula- 
ting in  large  numbers  on  the  smaller  sprouts  or  Hmbs  near  the 
ground  before  spreading  to  the  rest  of  the  tree  or  other  trees,  so 
that  prompt  treatment  when  first  observed  will  prevent  general 
infestation. 

Control. — Spraying  as  for  the  apple-aphis  (p.  537) ,  will  control 
the  pest. 

*  Myzus  cerasi  Fab.  Family  Aphididce.  See  C.  M.  Weed,  Bulletin  Ohio 
Agr.  Exp.  Sta.,  Tech.  Ser.,  Vol.  I,  No.  2,  p.  Ill;  C.  P.  Gillette,  Journal  of 
Economic  Entomology,  Vol.  I,  p.  362. 


596       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Cherry  Fruit-fly  t 

The  cherry  fruit-fly  is  a  native  insect  whose  maggot  Uves  in 
the  flesh  of  the  cherries,  causing  them  to  rot.  It  is  very  nearly 
related  to  the  apple  maggot  (p.  559)  which  it  very  closely  resembles 
in  both  appearance  and  Ufe  history.  Injury  by  it  has  been 
recorded  in  Massachusetts,  New  York,  Ontario,  Pennsylvania, 
District  of  Columbia,  Michigan  and  Iowa,  so  that  it  is  probably 
generally  distributed  over  the  northeastern  States.  Although 
its  native  food-plant  is  unknown  it  is  probable  that  it  lives  on  some 
wild  sour  cherry.     As  cherries  are  always  more  or  less  injured 


Fig.  523. — The  cherry  fruit-fly  (Rhagoletis  cingulata  Loew.):  a,  fly;  h,  maggot; 
c,  anterior  spiracles  of  same;  d,  puparium;  e,  posterior  spiracular  plates 
of  pupa — all  enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

by  the  plum  curcuho,  it  is  quite  probable  that  injury  by  this 
maggot  may  have  been  attributed  to  the  curcuho  and  its 
identity  passed  unnoticed.  Sour  and  subacid  varieties,  such  as  the 
Morello  and  Montmorency,  are  worst  injured,  but  black  cherries 
and  indeed  all  varieties  are  more  or  less  damaged. 

The  fly  is  shghtly  smaller  than  that  of  the  apple-maggot,  being 
about  one-sixth  inch  long  with  a  wing  expanse  of  three-eighths 
inch.  The  body  is  blackish,  the  head  and  legs  are  pale  yellowish- 
brown,  the  sides  of  the  thorax  are  marked  with  a  longitudinal 

t  Rhagoletis  cingulata  Loew.  Family  TrypetidcB.  See  M.  V.  Slingerland, 
Bulletin  172,  Cornell  Univ.  Agr.  Exp.  Sta.;  F.  H.  Chittenden,  Bulletin  44, 
Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  p.  70,  and  J.  F.  Illingworth,  Bulletin 
325,  Cornell  Agr.  Expt.  Station. 


INSECTS  INJURIOUS  TO  PEACH,  PLUM  AND  CHERRY      597 


yellow  band,  the  abdominal  segments  are  marked  with  whitish 
or  pale  brownish  transverse  bands,  and  the  wings  are  crossed  by 
four  blackish  bands.  The  maggot  is  about  one-quarter  inch 
long  and  is  indistinguishable  from  the  apple-maggot. 

Life  History.— The  eggs  are  deposited  just  under  the  skin 
of  the  cherry  from  June  until  August,  or  probably  during  the 
whole  season  of  the  fruit.  The  eggs  hatch  in  a  few  days  and  the 
little  maggots  penetrate  to  the  pits,  feeding  on  the  flesh  and 
forming  a  rotting  cavity  very  similar  to  that  made  by  the  grub  of 
the  curculio.  But  few  of 
the  affected  cherries  fall 
from  the  trees,  and  as 
thej^  frequently  show  but 
little  effect  of  the  damage, 
the  infested  fruit  may  be 
marketed  and  the  pest 
thus  spread.  When  full 
grown  the  maggots  leave 
the  cherries  and  form 
puparia  just  beneath  the 
surface  of  the  ground,  or 
in  the  bottoms  of  baskets 
or  in  rubbish,  wherever 
the  affected  fruit  may  be. 
The  flies  commence  to 
emerge  from  these  puparia 
by  the  middle  of  June  in 
New  York  and  are  found  during  the  summer  months. 

Control. — There  is  but  little  evidence  as  to  practical  means  of 
control.  Deep  plowing  in  spring  should  result  in  burying  the 
puparia  so  deeply  as  to  prevent  the  emergence  of  the  flies.  Culti- 
vation is  evidently  of  Uttle  value,  as  the  pest  occurs  in  well- 
cultivated  orchards,  so  that  shallow  cultivation  does  not  seem 
to  affect  the  puparia.  Chickens  have  been  observed  to  destroy 
the  puparia,  and  will  doubtless  prove  as  effective  as  against  the 
apple-maggot  where  they  can  be  confined  beneath  affected  trees 
on  cultivated  soil.     The  destruction  of  all  fruit,  whether  windfall 


Fig.  524.  —  Section  of  a  cherry,  enlarged  to 
show  the  maggot  of  the  cherry  fruit-fly  and 
nature  of  its  work.  The  small  figures 
above  show  the  maggot  and  parent  fly  nat- 
ural size.     (After  Slingerland.) 


598        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

or  remaining  on  the  tree  will,  of  course,  aid  in  control.  Recently 
a  nearly  related  fruit-fly  has  been  successfully  controlled  in  South 
Africa  by  spraying  the  foliage  with  arsenate  of  lead  sweetened  with 
treacle  or  brown  sugar,  thus  attracting  the  flies  which  are  poisoned 
by  the  arsenate,  and  this  method  is  worthy  of  trial  both  for  the 
cherry  ii  ait-fly  and  apple-maggot. 


CHAPTER  XXVII. 
SOME  INSECTS  INJURIOUS  TO  CITRUS  FRUITS* 
Scale  Insects  f 

There  are  many  scale  insects  injurious  to  citrus  fruit.  Possibly 
taken  collectively  they  are  the  most  important  pests  of  this  class  of 
fruit.  Their  importance  is  due  in  part  to  difficulties  encountered 
in  control  which  do  not  operate  in  the  control  of  scale  insects  on 
deciduous  trees.  Dormant  sprays,  the  main  dependence  for  scale 
control  on  the  latter  group  of  plants,  are  not  available  for  use 
against  citrus  scales.  It  will  not  be  feasible  to  discuss  all  the  im- 
portant scales  in  detail  here  but  the  two  natural  groups,  the 
armored  scales  and  the  unarmored  scales,  will  be  discussed 
separately. 

Armored  Scales  J 

There  are  several  armored  scales  which  are  important  pests  of 
citrus  trees.  Of  these  the  most  destructive  is  probably  the  Purple 
Scale  §  present  in  Florida  and  the  other  Gulf  States  and  in  Califor- 
nia. 

This  scale  resembles  the  common  oyster-shell  scale  of  the 
Southern  States.  It  is  found  for  the  most  part  on  citrus  fruits  and 
is  of  world-wide  distribution.  It  attacks  leaves,  twigs  and  fruit 
and  is  often  seen  on  fruit  in  northern  markets. 

The  California  Red  Scale  or  Orange  Scaled  is  more  important  in 

*See  H.  J.  Quavle,  Bulletin  214,  California  Exp.  Sta.;  J.  R.  Watson, 
Bulletin  148,  Florida  Exp.  Sta.;  W.  W.  Yothers,  Farmers'  Bulletin  933, 
U.  S.  Dept.  Agr.;  C.  E.  Wilson,  Quarterly  Bulletin,  State  Plant  Board  of 
Florida,  Vol.  II,  No.  1,  and  various  bulletins  from  the  Florida  Agr.  Exp. 
Sta.,  The  State  Plant  Board  of  Florida,  The  California  Agr.  Exp.  Sta.,  The 
California  State  Commission  of  Horticulture  and  the  U.  S.  Dept.  of  Agr. 

t  Family  Coccidcp.  See  list  of  publications  given  above  and  special  bul- 
letins mentioned  in  connection  with  the  different  scales. 

X  See  previous  reference. 

§  Lepidosaphes  beckii  Newman,  See  H.  J.  Quayle,  Bulletin  226  California 
Agr.  Exp.  Sta. 

H  Chrysomphaliis  aurantii  Mask.  See  H.  J.  Quayle,  Bulletin  222,  California 
Agr.  Exp.  Sta. 

599 


600      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

California  than  in  Florida,  but  is  present  in  Florida.  It  is  said  to 
be  second  only  to  the  black-scale  as  a  pest  in  California.  Adults 
of  this  scale  are  circular,  of  reddish  color  and  about  the  size  of  an 
ordinary  pin-head.  There  are  several  generations  in  the  course  of 
the  year  but  these  overlap  so  that  young  may  be  found  through  all 
the  season.     The  young,  like  those  of  the  San  Jose  scale  are  pro- 


FiG.  525. — Purple  Scale  on  lemon. 

duced  alive  and  not  hatched  from  eggs  as  is  usually  the  case  with 
scales. 

This  scale  attacks  trunk,  l:)ranches,  foliage  and  fruit  and  in- 
jures the  tree  by  sucking  the  juices  from  it.  It  also  injures  the 
appearance  of  the  fruit  upon  which  it  may  sometimes  be  seen  in 
the  market. 

The  Yellow  Scale  *  is  a  variety  of  the  California  Red  Scale  and 
differs  from  it  in  its  lighter  color  and  slightly  different  distribution. 

*  C.  aurantii  var.  citrinus  Coq. 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS 


601 


The  Long  Scale  *  is  one  of  some  importance  in  Florida,  but  is 
not  reported  from  California  as  a  pest.  It  is  similar  in  habits  and 
distribution  on  the  plant  to  the  Purple  Scale,  being  often  found  on 
the  fruit  with  that  scale,  but  it  may  be  distinguished  by  its  narrower 


Fig-  526.— The  Chaff  Scale  on  lemon. 

shape.     Being  about  the  same  length  as  the  purple  scale  it  is  much 

narrower.     They  are  not  always  distinguished  by  the  growers. 

A  scale  often  associated  with  the  red  and  yellow  scales  and 

similar  to  them  except  in  color^  which  is  more  of  a  light  gray,  is  the 

Greedy  Scale  f.     Its  main  injury  is  in  disfiguring  the  fruit  for 

market  as  it  rarely  interferes  seriously  with  the  growth  of  the  tree 

*  Lepidosaphes  gloverii  Pack.     See  Watson,  l.c 
t  Aspidiotus  camelliae  Sign  (or  rapax  Comstock) . 


602       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Similar  to  it  is  the  Oleander  Scale  *  which,  on  account  of  its  fre- 
quent occurrence  on  lemons  is  sometimes  called  the  lemon-peel 
scale.  The  two  latter  forms  are  common  in  Cahfornia,  but  not 
known  to  infest  citrus  in  Florida.  The  San  Jose  scale  (see  page 
470)  is  a  pest  in  both  localities,  but  does  not  do  as  much  damage  to 
the  citrus  fruits  as  it  does  to  the  deciduous  kinds,  being  largely 
over-shadowed  by  the  other  scales  mentioned. 

In  Florida  the  most  destructive  scale  is  the  Florida  Red  Scale 
or  Round  Scale  f.  It  lacks  importance  from  the  fact  that  it  is  not 
so  widely  distributed  as  some  of  the  others  and  does  not  seem  to 
spread  so  rapidly  or  to  be  as  generally  present  in  an  infested  plant- 
ing. This  scale  is  reddish  brown  in  color  with  a  lighter  brown 
center  and  is  nearly  circular.  It  infests  the  leaves  and  fruit  and 
will  easily  defoliate  a  tree  when  it  is  abundant. 

The  Chaff  Scale  J,  a  thin  gray  form,  sometimes  completely 
covers  the  bark  of  trees  in  Florida,  especially  the  bark  of  the 
smaller  branches.  The  Snow  Scale,  §  so  called  on  account  of  the 
white  color  of  the  males,  is  closely  related  to  the  scurfy  scale  of  the 
apple.  Neither  the  Chaff  Scale  nor  the  Snow  Scale  is  seriously 
injurious. 

The  Unarmored  Scales 

Members  of  this  group  lack  the  separable  scale  found  in  the 
previous  group  of  scales,  the  protection  to  the  body  being  provided 
by  a  thickened  and  sometimes  hardened  body- wall  rather  than  by 
a  secretion  from  the  body  wall.  They  are  generally  larger  than  the 
armored  scales  and  are  much  thicker  bodied,  their  shape  suggesting 
that  of  the  common  terrapin,  on  which  account  several  species 
receive  local  names  of  terrapin-scale  or  tortoise-scale. 

The  Black  Scale  f  is  the  most  important  of  the  scale  insects  in 
Cahfornia,  being,  according  to  Quayle,  the  most  destructive  of  the 
insects  attacking  citrus  fruits  in  that  state.  It  occurs  in  Florida 
but  rarely  attacks  citrus  plants  there,  being  more  common  on 
oleander  and  other  trees.  Its  injury  is  due  not  so  much  to  its  feed- 
ing habits  as  to  the  secretion  by  the  scales  of  a  substance  resembhng 

*  A.  hederae  Comstock. 
t  Chrysomphalus  aonidum  L. 
X  Parlatoria  pergandii  Comstock. 
%Chionaspis  citri  Comstock. 

'^Saissetia  olecB  Bern.     See  H.  J.  Quayle,  Bulletin  223  California  Agr. 
Exp.  Sta. 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS  603 

the  honey-dew  of  plant  lice  which  promotes  the  growth  of  a  black 
fungus,  known  as  the  sooty-mold  fungus,  on  the  leaves  and  fruit, 
and  makes  it  necessary  to  wash  the  fruit.  Washing  the  fruit 
involves  great  loss  due  in  part  to  the  cost  of  the  washing,  but  more 
to  the  infection  of  the  fruit  with  molds  through  abrasions  in  the 
skin  made  in  the  process.  The 
sooty-mold  fungus  on  the  leaves,  al- 
though it  Uves  from  the  honey-dew 
and  not  the  leaf,  interferes  with  the 
growth  of  the  leaf  by  forming  a 
dense  coating  over  it.  This  is  in- 
jurious to  the  leaf  and  to  the  tree. 

The  Black  Scale  is  large,  from  one- 
eight  inch  to  one-fourth  inch  long, 
more  or  less  hemispherical  in  shape, 
and  somewhat  wrinkled  or  ridged 
on  the  surface.  The  life  cycle  re- 
quires several  months  but  eggs  are 
produced  over  long  periods  and  in 
great  numbers,  as  many  as  3000 
from  one  female,  so  there  appears  to 
be  one  more  or  less  continuous  gen- 
eration. 

The  Soft  Brown  Scale,*  some- 
times called  the  Turtle  Back  Scale 
is  similar  to  the  one  just  discussed 
but  smaller,  of  a  brown  color  and 
lacking  the  darker  markings  of  the 

Black    Scale.       It    is    occasionally  fig.  527.— Black  Scale  (<Same<m 
locally  injurious  in  the  citrus  fruit  <'^^^  Bern.), 

region  and  is  present  over  a  large  part  of  the  country,  attacking 
a  variety  of  plants.  Its  injury  in  citrus  groves  is  due  to  the  honey- 
dew  and  consequent  growth  of  sooty-mold  fungus.  The  adult 
scales  are  somewhat  more  than  one-eighth  inch  long  and  the  shape 
is  less  nearly  hemispherical.  The  young  are  produced  alive,  eggs 
being  hatched  within  the  body  of  the  insect,  and  the  young  attack, 
by  preference,  the  young  growth.  There  are  three  or  four  broods. 
*  Coccus  hesperidum  L. 


604 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Hemispherical  Scale  *  is  essentially  a  greenhouse  pest, 
being  found  on  ornamental  plants  of  many  sorts  in  greenhouses. 
It  has  some  importance  as  a  pest  in  citrus  plantings  as  it  thrives 
outdoors  in  climates  suitable  for  orange  growth.  It  is  of  a  rather 
uniform  brown  color,  fairly  large  size  and  is  rather  smooth  and 
pohshed  on  the  surface. 

Other  scales  of  this  type  are  found  on  orange,  lemon  and  other 
trees  of  this  type  but  none  of  them  is  as  important  as  the  ones 

mentioned.  In  Flori- 
da, the  Wax  Scale 
(Ceroplastes  floriden- 
s?s  Comstock)  charac- 
terized by  a  thick 
covering  of  white 
wax,  and  two  other 
species  of  the  same 
genus,  are  frequently 
to  be  seen  but  rarely 
do  serious  damage. 

The  Cottony  Cush- 
ion Scale  or  Fluted 
Scalef  is  possibly  the 
most  famous  of  the 
scales  attacking  the 
citrus  plants.  While 
not  so  injurious  now 
as  formerly,  it  threat- 
ened, for  some  years 
after  its  introduction 
into  CaUfornia  in 
1868,  the  very  exist- 
ence of  the  citrus  in- 
dustry. Other  efforts 
to  control  it  having 
failed,  a  search  was  made  by  agents  of  the  Department  of  Agriculture 
at  Washington,  for  its  native  home,  in  the  hope  of  finding  there 
some  insect  which  fed  habitually  upon  it  and  was  capable  of  keep- 
ing it  in  check.     In  this  search  they  were  more  successful  than  other 

*  Saissetia  hemispherica  Targ. 
t  Icenja  purchasi  Mask. 


Fig.  528. — Hemispherical  scale,  Saissetia  hemis- 
phaerica. 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS 


605 


agents  have  been  in  recent  years  in  the  search  for  similar  enemies  to 
other  introduced  insects  for  they  found,  in  Australia,  which  appeared 
to  be  its  original  home,  a  lady-bug  beetle  which  fed  on  this  scale. 
Some  of  these  beetles  *  were  sent  to  California  where  they  were 
reared  and  distributed  to  the  infested  groves  and  in  a  few  years  had 
reduced  the  scale  to  the  status  of  an  occasional  pest  and  it  is  no  longer 
feared,  doing  less  damage  normally 
now  than  several  other  species  and 
being  always  easily  reduced  in  num- 
bers by  the  distribution  of  the  lady- 
bugs. 

The  Cottony  Cushion  Scale  is  more 
nearly  related  to  the  mealy  bugs  than 
to  the  soft-scales,  with  which  it  is 
usually  classed.  It  is  brown  in  color 
and  has  some  resemblance  to  the  soft 
or  unarmored  scales.  It  takes  its 
common  name  from  the  appearance  of 
the  females  at  egg-laying  time  when 
they  produce  underneath  the  posterior 
portion  of  the  body  a  mass  of  cottony 
wax  which  is  fluted  or  furrowed  on  the 
upper  side  and  forms  a  dense  cushion. 
In  this  cushion  the  eggs  are  laid.  At 
this  stage  the  scale  is  not  unUke  the 
common  cottony-maple  scale  of  the 
east  (Pulvinaria  innmnerahilis) . 

Recognition  of  this  species  is  easy 
on  account  of  the  appearance  of  the 
females.  Adults  are  found  on  the 
bark,  but  young  are  more  Ukely  to  be 
on  the  foliage.     There  are  three  or  four  annual  generations. 

The  scale  is  generally  distributed  in  California,  and  is  present 
in  many  locaHties  in  Florida.  While  the  lady-bugs  will  control  it, 
it  is  necessary  to  keep  watch  and  see  that  they  are  present  in 
infested  groves. 

*  Novius  (Vedalia)  cardinalis  Muls. 


Fig.  529. — Cottony  Cushion 
Scale. 


606 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


In  Florida  the  State  Plant  Board  collects,  rears  and  distributes 
these  lady-bugs,  to  the  growers,  a  nominal  charge  being  made  for 
the  service.  The  beetle  is  commonly  called  the  Vedalia  or  the 
Austrahan  lady-beetle. 

There  is  present  in  California  another  effective  parasite  of  the 
Cottony  Cushion  Scale,  a  true  fly,  of  the  family  AgromyzidcB 
(Gryptochaetum  monophlcBbi) .  This  was  introduced  from  AustraUa 
the  same  time  as  the  VedaHa  beetle. 

Control  of  Scales  in  Citrus  Groves 

Since  the  control  measures  employed  for  scale  insects  are 
essentially  the  same  as  those  for  the  whitefly  and  the  mealy-bugs 
discussion  of  them  will  be  deferred  and  will  follow  the  discussion  of 
those  insects. 

Mealy  Bugs  * 

Several  species  of  mealy-bugs  occur  in  citrus  plantings  as  well 
as  on  truck  and  other  crops  in  the  South  and  on  greenhouse  plants 


Fig.  530. — Lemon    infested   with    the    common    mealy-bug. 
After  Woglum   and   Neuls.   U.   S.   Dept.   of  Agr. 

and  some  outdoor  ornamentals  farther  north.  The  most  impor- 
tant of  these  is  the  Citrus  Mealy-bug  f  and  since  they  all  have 
much  the  same  habits  and  appearance  they  will  all  be  treated 

*  Family  Cocddce,  Sub-family  Dactylopiince. 
^  Pseudococcus  citri  Risso. 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS  607 

under  this  head.     The  mealy-bug  is  common  in  all  citrus  growing 
regions  and  is  at  times  a  serious  pest. 

It  attacks  many  plants,  but  prefers  the  citrus  fruits.  It  is 
found  on  all  the  growing  parts  of  the  plants,  but  prefers  sheltered 
situations  as  between  the  leaf-stem  and  the  stem.  It  also  gets  into 
crevices  in  the  bark  and  sometimes  clusters  on  the  stem  end  of  the 
fruits  and  between  fruits  which  are  hanging  against  each  other. 


Fig.  531. — A  group  of  common  mealy-bugs.    Enlarged  about  9  times. 
After  Woglum  and  Neuls,  U.  S.  Dept.  of  Agr. 

Mealy-bugs  secrete  a  form  of  honey  dew  in  which  grows  a  black 
sooty-mold  of  fungus  which  disfigures  the  fruit  and  renders  wash- 
ing, with  its  objectionable  features,  necessary.  If  not  washed  off 
the  fruit  they  will  remain  on  it  after  picking  and  continue  to  breed 
causing  loss  in  transit  or  storage. 

The  eggs  are  laid  in  a  mass  of  cottony  wax  secreted  by  the 
females  and  the  young  are  fairly  active.  The  adults  are  never 
permanently  attached  to  their  food-plant  as  are  the  scales.  They 
breed  more  or  less  continuously  but  there  are  several  generations. 


608       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

They  are  likely  to  be  more  abundant  in  dry  weather,  spring  and 
fall  in  Florida. 

The  insect  is  resistant  to  sprays,  being  protected  by  its  waxy 
covering  and  the  young  are  also  resistant  to  fumigation  so  that  the 
insect  is  hard  to  control.  It  will  however,  yield  to  persistent 
treatment  under  the  methods  to  be  described. 

Mealy-bugs,  like  most  of  the  other  important  citrus  insects,  are 
subject  to  the  attacks  of  many  kinds  of  parasitic  and  predaceous 
enemies  which  may,  under  favorable  conditions,  entirely  eliminate 
the  necessity  for  artificial  control  measures.  It  has  been  observed 
in  California  that  the  work  of  these  enemies  is  interfered  with  by 
the  Argentine  ant  *  which  drives  away  the  parasites  or  destroys 
them  in  some  stages.  It  is  therefore  frequently  of  advantage  to 
protect  the  infested  trees  from  these  ants,  either  by  banding  with 
some  substance  which  will  keep  them  out  of  the  trees,  as  sticky 
tree-tanglefoot,  or  by  poisoning  the  ants.  This  is  done  quite 
successfully  by  the  use  of  the  following  poison  as  recommended  by 
Woglum  and  Neuls  f  from  whom  the  following  directions  are  quoted : 

*'  To  free  trees  of  ants  the  ideal  procedure  would  be  to  eradicate 
these  insects  from  the  area  affected.  The  writers  have  not  carried 
on  any  such  tests,  but  the  published  results  of  work  carried  on  by 
the  Department  of  Agriculture  against  the  Argentine  ant  |  would 
indicate  the  feasibility  of  freeing  orchards  of  this  pest. 

The  procedure  followed  with  noteworthy  success  in  municipal 
control  work  was  the  distribution  throughout  the  affected  area  of 
a  poisoned  sirup  in  a  suitable  container.  A  paraffined  paper  bag, 
with  perforations  for  the  passing  of  ants,  containing  about  a  gill 
of  sirup,  was  used  as  a  container  for  naiUng  to  trees." 

"  The  sirup  is  made  as  follows: 

Granulated  sugar pounds — 15 

Water pints —  7 

Tartaric  acid  (crystallized) ounce — 3^ 

Boil  for  30  minutes.     Allow  to  cool. 

Dissolve  sodium  arsenite  (C.  P.) ounce — ^ 

*  Iridomyrmex  humilis  Mayr. 

t  Woglum  and  Neuls,  Farmers'  Bulletin  862,  U.  S.  Dept.  of  Agr. 

j  Barber,  E.  R.  The  Argentine  Ant:  Distribution  and  Control  in  the 
United  States,  U.  S.  Dept.  of  Agr.,  Bui.  377,  23  p.,  4  fig.  1916.  Newell, 
Wilmon,  and  Barber,  T.  C.  The  Argentine  Ant.  U.  S.  Dept.  of  Agr.,  Bui. 
Ent.  Bui.  122. 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS  609 

In  hot  water pint —  1 

Cool.     Add  poison  solution  to  sirup  and  stir  well.     Add 
to  the  poisoned  sirup: 

Honey pounds — 1^ 

Mix  thoroughly. 

"A  number  of  experiments  with  banding  in  orchards  infested 
with  the  Argentine  ant  have  proved  the  practicability  of  this  method 
of  keeping  trees  free  of  ants  during  their  active  season,  and  this 
method  of  control  is  recommended  as  the  most  effective  one  tried. 
Before  the  band  is  applied  the  tree  should  be  pruned  so  that  the 
lowest  branch  is  fully  a  foot  above  the  ground,  and  all  rubbish 
should  be  removed  from  beneath  the  tree  and  the  soil  cultivated 
to  destroy  all  grass  and  weeds.  The  only  banding  material  which 
has  given  satisfaction  is  a  mixture  *  made  up  as  follows: 

Finely  powdered  flowers  of  sulphur . .  .part  by  weight — 1 

Commercial  tree-banding  sticky  material 

parts  by  weight — 6 

"The  two  ingredients  are  mixed  together  thoroughly  with  a 
wooden  paddle  until  of  a  uniform  color  and  consistency.  That 
possible  injury  may  be  avoided,  this  is  not  applied  directly  to  the 
bark,  although  direct  application  of  the  commercial  sticky  tree- 
banding  material  alone  has  never  been  noted  in  CaHfornia  to  affect 
citrus  trees  seriously.  First  coat  the  trunk  with  a  thin  layer  of 
paraffin  and  apply  the  mixture  of  sulphur  and  sticky  tree-banding 
material  over  this.  Paraffin  that  has  a  high  melting  point  is 
preferable,  and  it  is  applied  with  a  brush  while  melted.  It  hardens 
almost  immediately,  after  which  the  mixture  just  referred  to  can 
be  applied  in  a  band  about  5  inches  wide  and  almost  one-fourth 
inch  thick.  A  single  application  of  this  material  has  kept  trees 
free  of  ants  for  several  months  during  warm  weather. 

"Ants  that  are  on  trees  at  the  time  of  banding  usually  drop  off 

within  a  day  or  two  unless  nests  are  in  the  trunk  or  branches.     If 

nests  are  present,  however,  they  should  be  destroyed  by  applying 

pyrethrum  or  some  other  ant  powder,  or  with  a  fine  spray  of  gasoHne 

from  a  plumber's  torch,  or  with  cresolated  emulsion  applied  with  a 

*Compounded  by  Mr.  J.  R.  Horton  of  the  Bureau  of  Entomology,  U.  S. 
Department  of  Agriculture.  (See  Horton,  J.  R.  Some  weatherproof  bands 
for  use  against  ants.  In  Mo.  Bui.  Cal.  State  Com.  Hort.,  v.  5,  no.  11,  p. 
419-421.     1916.) 


610       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


3-gallon  compressed-air  sprayer.     This  should  be  done  early  in  the 

morning,  while  the  ants  are  least  active. 

"Inspection  should  be  made  weekly  for  the  discovery  of  rein- 

festedtrees,the  bands 
being  renewed  where 
necessary  and  the 
branches  of  the  trees 
kept  from  coming  in 
contact  with  weeds 
or  the  ground." 

Whiteflies* 

The  whiteflies  are 
the  most  important 
of  the  insects  attack- 
ing citrus  fruits  under 
the  conditions  exist- 
ing in  Florida  but  are 
not  so  serious  in  Cal- 
ifornia, as  they  are, 
as  yet,  present  in  that 
state  in  only  one  or 
two  restricted  locali- 
ties. Indications  are 
that,  once  they  are 
established,  they  will 
be  as  important  there 
as  in  Florida. 

According   to 

Watson  (1.  c.)  there 

are  eight  species  of 

Fig.  532-Adults  of  the  common  white  fly  crowd-  whiteflies    attacking 

ing  the   under   surface   of   new   orange  leaves.     .  .  .° 

Adults   appear   slightly   less   than  normal  size.  Cltrus      fruits      in 

(Morrill  and  Back.)     U.  S.  Dept.  of  Agr.  Florida        Two  of 

these,  the  Common  Whitefly  f  and  the  Cloudy- Winged  WhiteflyJ 
are  pests   of  the   first  importance  while  a  third  is  occasionally 

*  Family  Aleurodidae. 

t  Dialeurodes  citri  R.  &  H. 

X  D.  citrifolii,  Morgan. 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS  611 

important  (the  Woolly  Whitefly*).  The  last  named  species  is  al- 
most perfectly  controlled  by  a  Hymenopterus  parasite, 

The  life  history  of  all  these  is  essentially  the  same,  as  are  their 
habits,  and  one  discussion  will  fit  all  reasonably  well. 

The  eggs  are  minute  objects  laid  on  the  under  side  of  the  leaves. 
The  young  crawl  about  and  begin  to  suck  sap,  staying  away  from 
the  light  as  much  as  possible.  They  soon  become  stationary,  like 
scales,  and  remain  so  until  the  growth  is  completed,  when  they 
transform  to  adults  which  are  minute  fly-Hke  insects  about  one- 
sixteenth  inch  long.  The  wings  are  white  and  covered  with  a  fine 
waxy  powder. 

Injury  from  whiteflies  is  the  result  of  their  feeding  habits  which 
drain  the  tree  of  its  sap  and  also  of  the  production  by  them  of 
quantities  of  honey-dew,  the  effect  of  which  is  exactly  the  same  in 
this  case  as  in  the  case  of  the  scale  insects  having  the  same  habit, 
that  is,  the  growth  of  sooty-mold  on  all  parts  covered  with  the 
honey-dew  and  the  consequent  interference  with  the  function  of 
the  leaf  and  the  necessity  which  arises  for  washing  affected  fruits 
with  the  attendant  loss  from  the  process.  Blackening  of  the  trees 
from  the  sooty-mold  is  the  most  prominent  sign  of  the  presence  of 
the  whiteflies  in  number. 

Control  of  Whiteflies  f 

Whiteflies  maybe  controlled  by  spraying  and  by  fumigation. 
The  practice  of  these  control  methods  as  appHed  to  whiteflies  does 
not  differ  materially  from  the  same  methods  as  used  for  scales  and 
mealy-bugs.  They  are  therefore  all  discussed  under  the  general 
head  dealing  with  control  measures  for  these  insects.  Another 
means  of  controlling  the  whitefly,  and  applicable  only  to  it,  is  the 
control  by  the  use  of  parasites  or  fungus  diseases  which  attack 
these  insects. 

There  are  four  of  these  diseases  which  are  most  important  in  the 

control    of  whiteflies,  with    but    one  exception  they  infect    the 

young  insects  only.     Of  these  the  most  important  is  the  Brown 

Fungus  {Mgerita  wehberi),  which  appears  as  brown  spots  on  the 

under  side  of  the  leaves.     A  young  whitefly  attacked  by  one  of 

these  spores  produces  a  growth  of  the  fungus  from  which  minute 

*  Aleurothrixus  howardii,  Quaintance. 

tSee  P.  H.  Rolfe  and  H.  S.  Fawcett,  Bulletin  119,  Florida  Exp.  Sta. 


612       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

threads  or  hyphae  extend  out  inevery  direction  and  carry  the  disease 
to  other  young  on  the  same  leaf  without  the  production  of  more 
spores.  The  hyphce  grow  around  the  edge  of  the  leaf  to  the  upper 
surface  and  there  produce  the  spores.  When  the  spores  are  pro- 
duced they  are  carried  by  the  wind  and  other  natural  agencies  and 
are  quite  likely  to  infect  all  the  flies  on  a  tree  or  even  in  a  grove. 

This  fungus  appears  mainly  in  the  late  summer  and  in  the 
autumn  and  grows  best  in  wet  weather.  It  attacks  both  the 
Common  Whitefly  and  the  Cloudy-Winged  Whitefly. 

The  Red  Fungus  or  Red  Aschersonia  {Aschersonia  aleyrodis), 
is  next  in  importance.  It  develops  in  and  on  the  young  fly  and 
does  not  send  out  the  hyphae  as  does  the  brown  fungus.  It  can 
therefore  be  carried  only  in  the  spore  form.  The  spores  are  formed 
in  small  pits  on  the  fungus  growth,  such  growths  being  called  fungus 
pustules.  This  species  thrives  earlier  in  the  season  than  does  the 
brown  fungus  and  it  also  is  effective  against  both  the  common 
species. 

The  Yellow  Fungus,  or  Yellow  Aschersonia  (Aschersonia  flavo- 
citrina)  is  interesting  as  well  as  important.  In  appearance  and 
growth  it  is  almost  exactly  like  the  red  fungus,  but  bright  lemon 
yellow.  It  affects  only  the  Cloudy-winged  Whitefly,  of  which  it 
is  an  important  parasite. 

The  fourth  species  of  importance  is  called  Microcera  (Fusarium) 
and  is  particularity  destructive  to  the  Cloudy-winged  Whitefly. 
It  attacks  several  of  the  scale  insects  as  well  as  the  whitefly  and  is 
of  importance  in  their  control.  It  grows  more  quickly  than  the 
other  fungi,  requiring  less  than  a  week  for  the  formation  of  spores 
where  the  other  species  require  nearly  a  month.  It  infests  young 
larvae  to  the  greatest  extent,  but  attacks  both  eggs  and  adults  as 
well.  It  thrives  better  during  cooler  weather  than  do  the  others, 
but  it  needs  plenty  of  moisture. 

All  fungi  do  best  under  rainy  weather  conditions,  and  it  is 
said  that  if  the  rainy  season  persisted  throughout  the  year  there 
would  be  no  need  for  artificial  measures  of  control  for  the  whitefly 
and  possibly  also  for  some  of  the  scales. 

Preservation  and  distribution  of  fungi. — These  fungi  may  be 
preserved  until  needed  by  placing  leaves  with  the  fungus  and 
spores  present  on  them  in  cold  storage  or  by  drying  the  leaves  and 
storing  them.     From  such  material,  cultures  may  be  introduced 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS  613 

early  in  the  season  before  fresh  fungus  is  available.  Special  di- 
rections for  this  should  be  obtained  from  the  State  Plant  Board 
or  the  State  Experiment  Station,*  (of  Florida). 

The  fungus  is  introduced  into  groves  or  trees  infested  with 
whitefly  but  free  from  fungus,  either  by  placing  infected  leaves 
in  and  about  the  trees  or  by  making  a  v/ater  infusion  from  the 
leaves,  thus  forming  an  infusion  of  the  sjjores  and  spraying  or 
sprinkling  this  on  the  under  side  of  the  leaves.  When  material  is 
scarce  the  infusion  may  be  placed  in  a  large  pan  or  bucket  and  the 
ends  of  a  few  branches  of  each  tree  dipped  into  this,  dependence 
for  further  spread  being  placed  on  the  natural  methods  of 
dissemination. 

The  recommendation  for  the  use  of  fungi  states  that  they  may 
not  always  be  depended  upon  for  complete  control,  but  that,  in 
the  best  practice,  use  should  be  made  of  them  in  connection  with 
the  use  of  the  contact  insecticides  described. 

Pure  Cultures  of  Fungi. — Of  the  several  fungus  parasites  of 
whiteflies  known  in  Florida,  two,  namely,  the  Red  Aschersonia 
and  the  Yellow  Aschersonia,  can  be  readily  grown  in  the  laboratory 
in  pm-e  cultures  on  sterilized  sweet  potato.  The  brown  fungus 
has  also  been  tried,  but  while  a  vegetative  growth  can  readily  be 
obtained  it  has  so  far  refused  to  produce  spores.  The  methods 
for  growing  these  fungi  in  pure  cultures  were  perfected  some  years 
ago  by  the  Florida  Experiment  Station.f 

When  in  1915  the  State  Plant  Board  of  Florida  was  organized, 
the  growing  of  pure  cultures  of  the  Red  and  Yellow  Aschersonias 
became  one  of  the  projects  of  the  Entomological  Department. 
Since  that  time  a  few  hundred  to  as  many  as  several  thousand 
cultures  have  been  annually  produced.  A  culture  consists  of  the 
amount  of  fungus  and  fungus  spores  that  can  be  grown  in  a  pint 
widemouth  bottle  and  is  sufficient  for  starting  fungus  in  an  acre 
grove.  More  or  less  may  be  used  but  the  amount  indicated  has 
been  found  to  be  quite  sufficient.  Sterilized  plugs  of  sweet 
potato  were  originally  the  medium  upon  which  these  fungi  were 
grown,  but  it  was  soon  discovered  that  the  addition  of  a  small 

*  See  E.  W.  Berger,  Bulletins  97  and  103,  and  J.  R.Watson,  Bulletin  123, 
and  Annual  Reports  for  1907  of  the  Entomologist  and  Pathologist,  Fla. 
Agr.  Exp.  Sta. 

t  See  H.  S.  Fawcett,  "Fungi  Parasitic  upon  Aleyrodes  citri,''  Special 
studies  No.  1,  Univ.  of  the  State  of  Fla.,  June  1908.  See  also,  E.  W.  Berger, 
p.  12,  Bulletin  103,  Florida  Exp.  Sta.,  1910. 


614       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

amount  of  agar  improved  the  consistency  of  the  cultures  so  that 
they  can  be  shipped  without  contents  of  the  bottle  becoming 
mixed  up,  or  disarranged.  The  presence  of  the  agar,  furthermore, 
permitted  allowing  the  contents  of  the  bottles  to  cool  and  harden 
in  a  sloping  position,  resulting  in  what  has  been  called  a 
"Sweet  potato-agar-slant"  which  has  certain  advantages  for 
manipulation  in  the  laboratory 

Control  of  Scale  Insects,  Mealy-bugs  and  Whitefly, 

Three  general  methods  for  the  control  of  the  above  insects  are 
used.  They  are,  spraying,  practiced  in  California  and  in  Florida 
with  equal  success;  fumigating,  practiced  in  Cahfornia,  but  not 
so  successful  under  Florida  conditions  on  account  of  the  large 
amount  of  rainfall;  and  control  by  the  encouragement  and  dis- 
tribution of  fungi  parasitic  on  the  insects,  this  method  being 
adapted  to  Florida  conditions  rather  than  to  those  which  obtain 
in  California,  since  these  fungi  usually  are  favored  by  excessive 
amounts  of  moisture. 

Spraying. — Spraying  for  the  insects  in  question  is  rather 
increasing  in  favor  as  new  methods  and  materials  are  being  per- 
fected. Formerly  it  was  considered  impossible  to  do  successful 
spraying  for  these  insects  because  of  the  close  heads  and  dense 
foliage  of  the  citrus  trees  and  their  lack  of  a  dormant  period 
which  would  permit  the  use  of  insecticides  stronger  than  the 
foliage  could  stand  and  would  also  permit  more  thorough  treatment 
of  the  trunk  and  branches  than  is  possible  where  the  tree  retains 
its  foliage  for  the  entire  year. 

However,  sprays  have  been  developed  which  will  kill  the  insects 
without  injury  to  the  foliage  and  there  are  spraying  machines  with 
which  these  sprays  can  be  applied  thoroughly  with  careful  labor. 
Lack  of  success  is  likely  to  be  due  to  faults  in  the  application  of  the 
sprays  rather  than  to  the  inefficiency  of  the  method. 

In  spraying  for  all  the  insects  in  this  list  several  things  must  be 
considered.  First  is  the  fact  that  these  are  all  sucking  insects 
which  must  be  hit  by  the  spray  to  be  killed;  second  is  the  fact 
that  there  are  several  stages,  some  of  which  are  more  easily  killed 
by  spray  materials  than  are  others  so  it  is  necessary  to  have  a 
reasonable  knowledge  of  these  stages  in  order  to  apply  the  sprays 
when  they  will  do  the  most  good ;  and  third,  the  fact  that  they 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS  615 

breed  and  increase  with  great  rapidity  so  that  a  few  individuals 
escaping  the  first  treatment  may  in  a  few  weeks  make  additional 
treatments  necessary,  even  with  the  most  efficient  spraying. 
Spray  materials  most  widely  used  are  the  oil  emulsions  and 
miscible  oils.  In  Florida  there  are  two  kinds  of  emulsions  used, 
called  the  boiled  emulsion  and  the  cold-stirred  emulsion.  Direc- 
tions for  making  these  are  given  by  Mr.  W.  W.  Yothers  in  Farmers' 
Bulletin  933,  U.  S.  Department  of  Agriculture,  and  are  quoted 
here  as  the  best  available: 

''Experiments  covering  a  10-year  period  have  shown  that  the 
best  insecticides  for  controlling  white  flies  and  scale  insects  are 
those  having  a  base  of  cheap  lubricating  oil  or  what  may  be  called 
'paraffin  oil.'  These  oils  are  made  into  emulsions  according  to 
the  formulas  following. 

"Fish-oil  soap  at  the  rate  of  from  5  to  8  pounds  to  50  gallons 
of  water  in  May,  or  from  12  to  16  pounds  to  50  gallons  of  water 
during  the  winter  season,  is  an  effective  spray  that  has  been  used 
for  many  years  without  injury  to  the  fohage  or  fruit. 

''While  both  the  fish-oil  soap  and  the  oil  emulsions  are  effective 
in  killing  the  whiteflies  and  scale  insects,  experience  indicates 
that  the  latter  are  far  superior  to  the  former  under  Florida  con- 
ditions. This  superiority  is  due  to  the  physical  properties  of  the 
oils.  The  high  boiling  point  and  great  viscosity  possessed  by 
these  oils  make  them  operative  over  a  longer  period  of  time  after 
application,  and,  too,  they  are  only  slowly  affected  by  average 
temperatures  and  showers.  Foliage  sprayed  with  miscible  oils 
remains  slightly  oily  in  appearance  and  to  the  touch  for  several 
weeks  after  apraying.  Fish-oil  soap  leaves  no  such  evidence 
that  the  trees  have  been  sprayed.  The  oil  spray  is  much  less 
affected  by  showers  than  is  the  fish-oil-soap  spray.  Summer 
showers  falling  after  the  oil  spray  has  once  had  an  opportunity 
to  dry  on  the  foliage  have  little  effect  in  lessening  the  efficiency 
of  the  spray.  Such  showers,  however,  have  a  very  evident  effect 
upon  the  number  of  insects  killed  by  the  soap  spray.  The  effective- 
ness of  the  weaker  strengths  of  fish-oil  soap  is  much  more  reduced 
by  showers  than  is  the  effectiveness  of  the  weaker  strengths  of 
oil  sprays. 

''In  experimental  work  on  a  large  scale  for  the  control  of  the 
citrus  white  fly  the  miscible-oil  sprays  have  given  better  results 


616       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

than  have  the  soap  sprays.  This  greater  efficiency  seems  to  be 
due,  not  to  a  higher  percentages  of  larvae  and  pupae  killed  when 
the  spray  is  applied,  but  to  the  effect  that  oil  sprays  exert  upon 
unhatched  eggs  or  upon  the  young  larvae  hatching  from  them 
within  10  to  14  days  after  spraying.  The  oil  forms  a  film  over  the 
eggs  which  prevents  a  large  percentage  from  hatching,  and  the 
young  larvae  from  those  which  do  hatch  are  killed  either  in  the 
act  of  emerging  from  the  shell  or  in  crawling  over  the  oil-coated 
leaf.  Those  who  are  in  touch  with  the  white-fly  problem 
appreciate  the  fact  that  no  matter  how  efficacious  an  insecticide 
may  be  in  killing  larvae  and  pupae  on  the  leaves  at  the  time 
the  spray  is  applied,  if  it  does  not  either  kill  these  unhatched 
eggs  or  remain  operative  long  enough  to  kill  the  larvae  that  sub- 
sequently hatch,  much  of  the  benefit  of  spraying  is  counter- 
balanced by  reinfestation. 

''There  are  two  ways  of  making  miscible-oil  emulsions: 
(1)  Without  heat;  (2)  with  heat.  The  first  is  called  the  'cold- 
stirred  emulsion'  the  second,  the  'boiled'  emulsion.  Both 
kinds  of  emulsion  are  efficient,  reliable,  and  easily  made. 

Cold-Stirred  Emulsion. 

T^.  ,     .,  Formula. 

Fish-oil  soap: 

By  weight     8  pounds 

By  measure 1  gallon 

Paraffin  oil,  24   or  28   Baume 2  gallons 

Water 1  gallon 

''Directions  for  preparation. — In  preparing  the  stock  mixture," 
the  soap  should  be  put  into  a  receptacle  of  about  five  gallons 
capacity  and  the  oil  added  while  the  mixture  is  being  vigorously 
stirred.  It  is  important  that  the  oil  be  added  in  small  quantities 
at  first,  and  that  the  stirring  be  sufficient  to  keep  the  oil  and  soap 
in  the  form  of  an  emulsion  after  each  addition  of  oil.  Thus,  at 
first  about  a  pint  of  oil  should  be  added  to  the  soap  and  the 
mixture  stirred  until  no  free  oil  appears.  As  the  amount  of  oil  is 
increased  it  should  always  be  stirred  or  mixed  thoroughly  before 
the  next  addition  is  made.     After  the  required  amount  of  oil 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS  617 

has  been  added  and  after  free  oil  has  ceased  to  appear  on  top  of  the 
soap,  the  water  is  slowly  poured  in,  about  1  quart  at  a  time 
As  previously  stated,  the  only  apparatus  required  to  make  this 
formula  in  a  small  way  is  an  ordinary  galvanized  iron  pail  and  a 
paddle. 

"The  foregoing  formula  may  be  modified  under  certain  con- 
ditions, as  the  quantity  of  soap  will  depend  largely  upon  the  time 
consumed  in  adding  the  oil  and  the  amount  of  stirring;  the  amount 
of  soap  being  lessened  if  the  stirring  be  uniform  and  ample  time 
be  taken  in  the  careful  preparation. 

If  it  be  desired  to  make  this  formula  on  a  large  scale,  a  300- 
gallon  cyHndrical  tank  may  be  fitted  with  paddles,  which  are 
attached  to  a  shaft  in  a  vertical  position,  occupying  the  center 
of  the  tank.  The  shaft  is  fitted  with  a  beveled  gear  on  the  upper 
end.  A  horizontal  shaft  is  then  connected  with  the  vertical  shaft 
by  means  of  another  beveled  gear,  while  the  other  end  has  a 
pulley  to  connect  with  the  engine.  A  series  of  brakes  should  be 
fitted  to  the  sides  of  the  tank  to  prevent  the  entire  mass  from 
turning  around  with  the  paddles.  An  entire  barrel  of  fish-oil 
soap  may  be  placed  in  this  tank  and  the  stirring  begun  at  once. 
Two  barrels  of  oil  may  then  be  run  into  the  soap  through  an 
inch  or  l|-inch  hole  in  the  end  of  the  barrel,  or  the  oil  may 
be  run  out  of  the  bung-hole.  After  the  oil  has  been  added, 
either  one-half  or  two-thirds  of  one  barrel  of  water  can  be  added 
to  complete  the  preparation  of  the  stock  solution.  In  the  final 
spray  this  should  be  so  diluted  as  to  contain  about  1  per  cent  of 
oil  by  adding  1  gallon  of  the  stock  solution  to  50  gallons  of  water. 

"It  is  also  highly  practicable  to  fit  up  a  50-gallon  barrel  in  the 
same  way  as  described  above  for  the  300-gallon  tank.  By  attaching 
a  crank  to  the  horizontal  shaft  the  mixer  can  be  run  by  hand  instead 
of  by  an  engine.  Such  a  mixer,  designed  and  used  by  Mr.  J.  A. 
Stevens,  De  Land,  Fla.,  has  been  found  practicable.  The  writer 
has  used  an  ice-cream  freezer  for  making  an  emulsion,  by  removing 
the  can  and  adding  a  false  bottom  of  1-inch  board  to  hold  up  the 
stirring  gears.  In  fact,  manj^  different  types  of  mixers  can  be 
constructed,  depending  on  the  material  available  and  the  scope  of 
the  work  involved. 


618       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Boiled  Emulsion. 

Formula. 

Paraffin  oil 2  gallons 

Water 1  gallon 

Fish-oil  soap      2  pounds 

or 

Hard  soap      2  pounds 

"Directions. — Put  oil,  water,  and  soap  into  a  kettle  or  other 
vessel  that  will  stand  fire,  and  heat  to  the  boiling  point.  While 
still  very  hot,  pump  the  material  into  another  vessel  and  then  back 
again.  Emulsion  can  not  be  made  by  this  formula  without  a 
pump;  stirring  is  not  sufficient. 

"Dilute  to  make  200  gallons  of  spray  material. 

"For  making  the  above  formula  the  writer  has  used  9  and  15- 
gallon  kettles,  wash  boilers,  and  100-gallon  oil  tanks  with  uniform 
success. 

"If  it  is  desirable  to  make  this  formula  on  a  somewhat  larger 
scale,  the  materials  can  be  heated  in  a  large  kettle  or  other  vessel 
and  then  dipped  into  a  barrel  pump  outfit  and  the  mixture  emulsi- 
fied by  pumping  it  back  upon  itself.  For  safety  it  is  best  to  have 
all  the  material  pass  through  the  pump  twice,  but  it  must  not  be 
pumped  after  it  has  become  cool.  Excessive  pumping  will  break 
up  a  good  emulsion.  It  can  also  be  heated  in  a  large  galvanized 
oil  tank  having  a  capacity  of  4  barrels  and  emulsified  by  means  of 
the  spraying  machine.  In  this  case  the  suction  hose  should  be 
put  into  the  tank  of  hot  material  and  the  discharge  hose  into  the 
spray  tank.  For  the  second  pumping,  put  the  suction  hose  into 
the  spray  tank  and  the  discharge  hose  into  the  storage  barrels. 
When  the  spraying  machine  is  used  for  this  purpose,  an  old  suction 
hose  should  be  used,  as  well  as  a  discarded  piece  of  hose  for  the 
discharge  end.  This  should  be  not  more  than  10  feet  in  length. 
The  material  should  be  run  through  an  ordinary  nozzle  with  the 
disk  left  off.     The  overflow  will  not  emulsify  this  material. 

"Owing  to  the  high  temperature  of  the  mixture,  pumps  used 
for  emulsifying  should  have  metal  valves.  If  made  of  other 
material  their  period  of  usefulness  is  very  short.  It  should  always 
be  remembered  that  a  pressure  pump  must  be  used  for  emulsifying. 
The  writer  has  never  succeeded  in  making  an  emulsion  with  a 
rotary  pump. 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS  619 

"Difficulties  that  may  arise  in  making  the  boiled  formula  are: 
(1)  A  lack  of  sufficient  heat;  (2)  improper  pumping;  (3)  an  improper 
emulsifier.  In  many  tests  the  water  and  soap  only  were  heated, 
and  failure  to  produce  a  perfect  emulsion  resulted  in  every  instance. 
On  the  other  hand,  when  all  the  materials  were  heated  together  a 
perfect  emulsion  was  secured.  The  materials  should  be  heated 
until  a  slight  foam  or  a  few  bubbles  appear,  but  it  is  not  necessary 
to  boil  for  any  length  of  time. 

"  Some  growers  have  failed  because  they  attempted  to  stir  the 
materials  together  with  a  stick,  and  others  because  they  used  a 
rotary  pump.     Neither  of  these  is  satisfactory. 

*'  The  emulsifying  agent  is  very  important.  There  is  no  doubt 
that  potash  fish-oil  soap  is  the  most  satisfactory  of  all  soaps  for 
the  making  of  any  of  these  emulsions.  When  this  material  is 
used  the  oil  very  seldom  separates  and  the  resulting  emulsions 
never  become  too  thick  to  be  poured  or  handled  conveniently. 
On  the  other  hand,  when  hard  soaps  are  used  which  are  made 
from  caustic  soda  and  fats  containing  large  proportions  of  stearin 
and  small  quantities  of  resin,  the  emulsions  separate  on  cooling, 
and  will  cause  much  trouble  in  mixing  on  the  day  after  they  are 
made.  If  the  emulsion  made  from  any  hard  soap  found  on  the 
market  is  used  on  the  same  day  that  it  is  made  no  trouble  will  be 
experienced.  The  'cold-stirred'  formula  is  difficult  to  make  with 
hard  soaps.  The  writer  has  found  it  impossible  to  make  emulsions 
by  using  any  of  the  soap  powders,  even  if  flour  is  used  as  a 
stabilizer. 

"Before  any  spray  material  is  applied  to  a  tree  it  should  be 
tested  to  determine  if  it  is  a  perfect  emulsion.  To  do  this,  add 
a  small  amount  to  some  soft  water;  if  no  oil  floats  or  no  thick, 
greasy  scum  forms,  it  is  satisfactory.  If  free  oil  appears  the 
emulsion  is  imperfect  and  should  not  be  used.  Great  care  should 
be  used  to  stir  the  contents  of  the  barrel  thoroughly  before  any 
test  is  made. 

"Just  at  present  the  boiled-emulsion  formula  is  the  one  which 
will  appeal  to  the  average  citrus  grower  in  Florida.  It  is,  beyond 
all  question,  the  cheapest  effective  insecticide  for  white  flies  and 
scale  insects. 

"The  oils  used  in  the  making  of  these  formulas  usually  test 
from  24°  to  32°  Baume  and  have  a  viscosity  not  less  than  200. 


620  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  best  oils  for  spraying  purposes  have  a.  viscosity  of  about  300 
to  400  and  they  may  be  purchased  from  any  of  the  oil  companies 
operating  in  the  citrus-growing  belt.  Petroleum  fuel  oil  and 
distillate  or  gas  oil  may  also  be  used  and  when  applied  should  be 
used  at  twice  the  strength  indicated  for  the  lubricating  oils. 
The  soaps  may  be  purchased  from  any  grocery  or  fertilizer 
company. 

Proprietary  Miscible  Oils. 

"There  are  several  proprietary  miscible  oils  on  the  market 
which  the  writer  has  found  to  give  highly  satisfactory  results. 
These  should  be  diluted  so  that  the  spray  material  will  contain 
somewhere  between  3^  per  cent  and  1  per  cent  of  oil.  Th6  writer 
would  advise  the  use  of  oil  emulsions  when  diluted  to  about  1 
per  cent.  Experience  indicates  that  such  substances  as  rosin 
oil  and  sulphuric  acid  should  not  be  used  in  proprietary 
insecticides." 

Use  of  Fungus  Diseases. — A  method  for  the  control  of  some 
citrus  insects,  particularly  the  whiteflies,  in  Florida,  is  the  artificial 
dissemination  of  fungus  spores  causing  certain  fungus  diseases 
to  which  these  insects  are  susceptible.  The  discussion  of  the 
fungi  and  methods  used  is  included  with  the  discussion  of  the 
whiteflies  as  this  method  is  not  so  extensively  used  for  other 
insects. 

There  are,  however,  four  *  principal  fungus  parasites  or  dis- 
eases, of  scales  that  are  at  times  very  effective  in  the  natural 
control  of  citrus  scales  in  Florida  and  the  Gulf  Coast.  These  are 
the  Red-headed  Scale-fungus  {Sphaerostible  coccophila  Tul)  the 
White-headed  Scale  fungus  (Ophionectra  coccicola  E.  &  E.),  the 
Black  Scale  fungus  (Myriangium  duriaei  Mont),  and  the  Pink 
Scale  fungus  (Microcera  fujikuroi  Miyabe  &  Sawada) . 

The  first  of  these  infects  and  kills  the  purple  scale,  long  scale  and 
chaff  scale  and  several  scales  infesting  deciduous  trees,  including 
the  San  Jose;  the  second  infects  the  purple  scale  and  long  scale; 
the  third  the  purple  scale,  chaff  scale,  long  scale  and  San  Jose  Scale; 
the  fourth  the  Florida  red  scale  and  purple  scale. 

*  See  P.  H.  Rolfs  and  H.  S.  Fawcett,  Bulletin  119  (Revision  of  94).  Fla. 
Exp.  Sta.  for  the  first  three  fungi  named  herewith.  See  J.  R.  Watson,  Report 
of  Entomologist,  Annual  Report  194,  Fla.  Exp.  Sta.  for  the  4th  or  pink  scale 
fungus. 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS  621 

These  fungi  are  generally  introduced  or  distributed  in  scale- 
infested  trees  by  tying  small  pieces  of  fungus  material  (2  or  3  inches 
long)  to  twigs  or  branches  having  the  most  scale.  The  fungus 
material  may  also  be  rubbed  up  in  water  and  the  resulting  infusion 
of  spores  and  water  sprayed  into  the  trees  or  mixed  with  the 
infusion  of  spores  used  for  distributing  the  whitefly-fungi 

Fumigation.* 

By  all  means  the  most  popular  and  efficient  means  of  control 
for  citrus  fruit  insects  in  California  is  fumigation  with  hydrocyanic 
acid  gas.     General  discussion  of  the  nature  of  this  gas  and  its 


Fig.  533. — Fumigation  of  citrus  trees.     Some  steps  in  preparation.     After 
Woglum,  U.  S.  Dept.  of  Agr. 

preparation  will  be  found  in  the  chapter  on  insecticides  in  this 

volume.     The  application  of  the  process  to  outdoor  conditions  for 

use  to  kill  insects  on  trees  is,  in  itself,  a  matter  of  special  study. 

The  work  in  California  is  usually  done  by  contract  by  concerns 

which  make  that  work  their  business,  but  the  grower  should  have 

an  idea  of  the  nature  of  the  process  in  order  to  be  able  to  tell 

whether  the  work  is  being  done  properly. 

The  fumigating  season  extends  from  August  to  January  and 

the   work    should  be   done  when  the  temperature  is  not  either 

unusually  high  or  unusually  low.     It  is  usually  done  during  the 

night. 

*See  R.  S.  Woglum,  Farmers'  Bulletin  823,  U.  S.  Dept.  of  Agr.  and 
bulletins  of  the  California  Agr.  Expt.  Station. 


622       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  method  consists,  essentially,  of  the  enclosure  of  the  trees 
to  be  treated,  in  individual  tents  made  of  material  as  nearly  im- 
previous  to  the  gas  as  possible  and  of  generating  in  the  tents  gas 
according  to  a  variable  table,  based  on  the  cubic  content,  the 
amount  of  leakage,  which  latter  is  less  in  proportion  for  large  trees 
than  for  small,  and  upon  other  factors.  Very  accurate  dosage 
tables  have  been  worked  out  and  are  available  wherever  fumigation 
is  a  common  practice.  Time  of  exposure  to  the  action  of  the  gas 
is  from  45  minutes  to  one  hour,  the  same  as  for  deciduous  trees 
being  fumigated  in  houses  for  San  Jose  Scale. 

Special  machinery  for  the  generation  of  the  gas  is  used  by  the 
large  fumigating  concerns.  With  these  the  gas  is  generated  out- 
side the  tents  and  piped  into  them  and  the  necessity  for  separate 
generating  outfits  for  each  tent  is  done  away  with. 

Fumigation  has  been  tried  rather  extensively  in  Florida,  but 
not  so  well  adapted  for  Florida  conditions  as  for  those  in  California 
and  so  is  not  recommended  for  use  in  Florida. 

As  mentioned  before  in  connection  with  fumigation,  it  should 
not  be  undertaken  except  under  the  direction  and  advice  of  experts 
as  otherwise  there  is  danger  to  the  trees  and  to  the  operator. 

The  Citrus  Thrips.* 

The  Citrus  Thrips  is  one  of  the  smallest  members  of  a  group  in 
which  the  largest  species  are  considered  as  minute  insects.  It  has 
been  known  to  be  injurious  to  citrus  fruits  for  a  quarter  of  a  century 
but  the  injury  was  not  generally  recognized  until  about  ten  years 
ago,  on  account  of  the  small  size  of  the  insect.  So  far  as  is  now 
known  it  is  confined  almost  entirely  to  California  and  is  not  found 
in  the  gulf  states.  In  Florida  a  different  species,  the  Florida 
Flower  Thrips  f  is  similarly  injurious. 

The  thrips  sucks  the  juices  from  foliage  and  fruit  and  kills  the 
cells  surrounding  its  puncture.  These  dry  up  and  form  character- 
istic scabs  and  much  of  the  injury  is  due  to  their  thus  scabbing  the 
fruit,  especially  around  the  stem  end  where  they  cause  a  condition 
described  as  "stem-end  ring."  They  also  cause  curling  of  the 
leaves  and  a  grayish  discoloration  and  interfere  in  this  way  with 

*  Sdrtothrips  citri  Moulton.  See  J.  R.  Horton,  Bulletin  616,  U.  S.  Dept. 
of  Agr. 

t  FranklinieUa  hispinosus  Watson. 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS 


623 


the  growth  of  the  plant.  Injury  to  young  fruits  often  results  in  a 
large  amount  of  dropping.  Splitting  and  other  deformation  of  the 
fruit  is  another  evil 
effect  of  thrips  in- 
jury. 

The  California 
thrips  is  trans- 
ported  from  place 
to  place  for  the  most 
part  on  young  trees 
where  it  is  present 
in  the  egg  stage. 
Local  spread  is  the 
result  of  the  flight 
of  the  adults.  It 
is  not  confined  to 
the  citrus  plants, 
but  feeds  on  several 
others  such  as 
grape,  pomegran- 
ate and  apricot  and 
these  may  serve  as 
sources  of  infesta- 
tion. The  life  cycle 
requires  about  a 
month  and  there  Fig.  534 
are  from  six  to  eight 
generations  which  overlap  so  that  they  are  practically  indistin- 
guishable. The  winter  months  are  passed  in  the  egg  stage.  The 
Florida  flower  thrips  is  present  everywhere  and  infests  the 
blossoms  of  many  plants. 

Control. — Natural  enemies  are  an  important  factor  in  thrips 
control.  They  include  larvae  of  the  lace-wing  flies  (Chrysopa 
californica  Coq.),  lady-bug  larvae,  some  of  the  assassin-bugs 
{Reduviidce)  several  species  of  spiders  and  a  fungus  disease.  In 
some  years  these  enemies  will  render  artificial  control  measures 
unnecessary. 

Spraying  is  resorted  to  for  control  where  any  artificial  measures 


y////////^ 


Citrus  Thrips :  a,  Young  nymph ;  h,  Full  grown 
nymph;  c,  Adult.  After  Horton,  U.  S.  Dept.  of  Agr. 


624       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


are  necessary.    Horton  1.  c,  summarizes  the  spraying  recommenda- 
tions based  on  spraying  tests  made  in  California  as  follows: 

"In  the  tests  the  following  insecticides  and  combinations  gave 
the  best  results.  Any  of  these  mixtures  may  be  reUed  upon  to 
give  satisfactory  control  when  properly  applied. 

1.  Lime-sulphur  solution. — If  the  lime-sulphur  is  of  a  density 
of  36°  Baume,  dilute  1  gallon  with  56  gallons  of  water;  if  of  a 
density  of  33°  Baume,  dilute  1  gallon  with  50  gallons  of  water. 

2.  Sulphur-soda  solution. — Two  gallons  of  the  stock  solution, 
prepared  as  described  diluted  with  25  gallons  of  water.  * 

3.  Lime-sulphur  and  tobacco  extract  (40  per  cent  nicotine 
sulphate). — Dilute  1  part  of  the  lime-sulphur,  if  34  to  36°  Baume, 


Fig.  535. — Graphic  illustration  of  the  seasonal  activities  of  the  citrus  thrips 
as  related  to  blossoming  and  later  growth  periods  of  the  orange  and 
indicating  also  the  spray  periods.     After  Horton,  U.  S.  Dept.  of  Agr. 

with  86  parts  of  water;  if  30  to  33°  Baume,  with  75  parts  of  water. 
Then  add  1  part  of  the  tobacco  extract  to  1,000  parts  of  the  lime- 
sulphur  as  diluted  above. 

4.  Tobacco  extract  (40  per  cent  nicotine  sulphate). — Dilute  1 
part  with  800  parts  of  water. 

Lime-sulphur  and  soda-sulphur  solutions  are  more  effective 

against  the  citrus  thrips  than  any  other  mixture  thus  far  tested, 

and  particularly  the  lime-sulphur  at  the  strength  stated  above- 

*  The  sulphur-soda  solution  was  prepared  as  follows : 

Powdered  sulphur 30  pounds 

Powdered  caustic  soda  (98  per  cent) 15  pounds 

Water  to  make 30  gallons 

The  sulphur  was  made  into  a  paste  with  water  and  the  soda  added,  while 
the  mixture  was  constantly  stirred,  in  sufficient  quantity  to  cause  boiling, 
a  little  water  being  added  occasionally  to  retard  the  cooking.  When  all 
the  sulphur  was  dissolved,  enough  cold  water  was  added  to  make  a  stock 
solution  of  30  gallons.  A  clear,  amber  liquid,  much  resembling  good  lime- 
sulphur,  was  the  result. 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS  625 

A  large  percentage  of  the  thrips  can  be  killed  by  spraying  with  this 
solution,  and  there  is  a  further  effectiveness  due  to  its  decompo- 
sition for  a  long  period  after  deposition  on  the  leaves.  In  orchards 
sprayed  with  good  lime-sulphur  the  sulphurous  odor  is  often  strong 
for  two  months  or  more  after  the  applications.  The  decomposition 
products  repel  the  thrips,  which  are  slower  to  reinfest  orchards  so 
sprayed  than  those  sprayed  with  solutions  that  soon  evaporate 
and  leave  no  trace. 

"Tobacco  extracts  when  used  at  the  proper  strengths  are 
also  very  effective.  Both  tobacco  extract  and  lime-sulphur, 
when  mixed  together,  are  effective  in  weaker  solutions  than  when 
diluted  with  water  alone.  Contrary  to  expectation,  the  addition 
of  soaps  to  tobacco  extract  did  not  give  increased  value  to  the 
tobacco  in  these  tests.  Soap  solutions  used  alone  appear  to  be 
worthless  at  the  dilutions  tested. 

"Resin  wash  at  any  strength  practicable  for  use  on  the  orange 
trees  in  this  section  is  worthless.  At  the  greatest  strength  used 
in  these  experiments  it  failed  to  reduce  thrips  injury  to  an  extent 
worthy  of  attention.  It  is,  furthermore,  very  injurious  to  fruit 
and  foliage. 

"Plain  water  spraying  was  utterly  ineffective,  demonstrating 
that  merely  striking  the  thrips  with  a  Hquid  at  high  pressure 
to  wash  them  from  the  trees  has  no  appreciable  effect  in  dimin- 
ishing their  numbers.  A  few  hours  after  spraying  with  water 
there  remained  on  the  trees  as  many  living,  active  thrips  as 
before  spraying." 

The  Florida  Flower  Thrips  * 

The  Florida  Thrips  is  larger  than  the  true  citrus  thrips,  being 
about  one  twenty-fifth  of  an  inch  long  while  the  other  is  frequently 
less  than  one-half  that  size.  It  is  of  a  yellowish  or  yellowish-red 
color  and  may  be  observed  most  easily  in  or  about  the  blossoms 
of  the  orange.  It  injures  the  fruits  and  plants  in  much  the  same 
way  as  does  the  citrus  thrips  but  is  more  likely  to  destroy  the 
blossoms  or  the  fruit  just  as  it  is  setting  by  making  its  way  down 
into  the  flower  to  the  ovary  which  it  attacks.     Its  injury  is  more 

*Frankliniella  bispinosus  Watson. 


626       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


noticeable  where  there  is  a  light  amount  of  bloom,  where  the 
bloom  is  heavy  the  injury  serves  in  a  way  as  a  natural  thinning 

and  may  be  beneficial.  Dis- 
figuring of  the  fruit  is  a 
source  of  some  loss  from 
this  insect.  The  Hfe  his- 
tory resembles  that  of  the 
citrus  thrips  but  the^e  are 
probably  more  generations. 
They  may  be  controlled, 
where  control  measures  are 
essential,  by  the  methods 
outlined  for  the  citrus 
thrips. 


Fig.  536. — Florida  Flower  Thrips.  From 
Watson  after  Dozier.  Enlarged  (Florida 
Agr.   Exp.   Sta.). 


^^ 


The  Rust-mite  or  Silver-mite  * 

According  to  Watson,  the  rust-mite  is,  in  Florida,  out-ranked 
as  a  pest  only  by  the  white  fly  and  the  purple  scale.  In  Cali- 
fornia it  is  less  important  being  restricted  in  its  distribution,  and 
called  the  "Silver-mite"  on  account 
of  its  silvering  effect  on  lemons.  It  was 
imported  into  Cahfornia  from  Florida. 

The  rust-mite  is  just  visible  to  the 
unaided  eye,  is  rather  elongate  and 
broader  at  the  anterior  end,  tapering 
to  a  rather  long  point  toward  the 
posterior  end. 

The  eggs  are  few  in  number  but 
hatch  in  a  short  time  and  the  life 
cycle  may  take  a  period  as  short  as 
two  weeks.  In  consequence  the  mul- 
tiplication, during  favorable  seasons  is 
very  rapid.  The  broods  are  inseparable. 

Mites  injure  the  foliage  by  sucking 
oils  from  the  cells  and  in  this  way  in- 
jures the  trees.  Their  chief  injury  is, 
however,  to  the  fruit  which  they  at- 
tack in  the  same  way.     Here  they  cause 


Fig 


537. — Orange  rust-mite: 
a,  dorsal  view;  b,  lateral 
view,  enlarged,  the  dot  in 
circle  indicating  natural  size ; 
c,  leg;  d,  egg  with  embryo 
just  about  ready  to  hatch 
more  enlarged.  (After  Hub- 
bard) U.  S.  Dept.  of  Agr. 


*  Eriophyes  oleivorus  Ashmead.     See   H.   J.   Quayle,   Bulletin  234,   Cal. 
Exp.  Sta.     Class  Arachnida,  order  Acarina,  Family  Eriophyidcp. 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS  627 

arusseting  of  the  fruit  which  reduces  its  quality  mainly  by 
detracting  from  its  appearance  but  also  by  reducing  the 
size.  Oranges  and  grapefruit  are  the  greatest  sufferers  in 
Florida.  Russeted  fruits  may  frequently,  even  now,  be  seen  on 
the  market. 

Control  of  the  Rust  Mite. — Weather  conditions  are  a  factor  in 
the  check  of  the  mites,  cold  and  wet  weather  being  unfavorable 
to  their  development.  These  can  not  be  relied  upon  to  prevent 
damage  and  spraying  is  practiced  wherever  the  mites  are 
abundant. 

Sulphur  is  the  best  insecticide  for  these  pests.  It  may  be 
applied  in  the  form  of  a  dust,  mixed  with  hydrated  lime  which 
is  used  as  a  carrier,  at  the  rate  of  one  part  lime  to  three  parts 
sulphur.  The  dusting  outfits  discussed  in  the  chapter  devoted 
to  spraying  apparatus  are  suitable  for  use  in  applying  this  material, 
but  care  must  be  used  to  see  that  the  dust  carries  through  the 
dense  foliage  of  the  trees. 

Free  sulphur  mixed  with  water  or  with  water  and  soap  is 
a  good  spray  for  the  mite.  Four  or  five  pounds  of  sulphur,  four 
pounds  of  soap  and  fifty  gallons  water,  are  about  the  proper 
proportions. 

Commercial  lime-sulphur  testing  32°,  Baume  scale,  should  be 
diluted  with  seventy-five  parts  of  water  and  will  make  a  very 
good  treatment  for  the  mites. 

Soda-sulphur  spray,  made  as  described  for  the  control  of  the 
thrips  and  diluted  at  the  rate  of  one  to  forty,  is  another  effective 
spray. 

Thoroughness  is  as  important  as  for  the  treatment  of  other 
citrus  pests. 

Red  Spiders  * 

These  pests  are,  like  the  mites,  members  of  the  class  Arachnida 
and  the  order  Acarina,  being,  in  fact,  true  mites  themselves. 
They  are  larger  than  the  rust  mites  and  one  species  is  quite  red 
in  color,  being  called  the  Florida  red-spider,  while  the  other  is 

*  Tetranychus  mytilaspidis  Riley  (or  T.  citri  McGregor. )  and  T.  sex- 
maculatus  Riley.     See  H.  J.  Quayle  (1.  c). 


628       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


more  greyish  and  has  six  dark  spots  which  suggest  the  specific 
name  and  the  common  name  of  the  six-spotted  mite. 

Red-spiders  are  common  in  the  spring  or  during  dry  weather. 


Fig.  538. — Red-spiders:  The  Citrus  Red-spider,  on  the  left;  The  Six-spotted 
mite  on  the  right.     After  Quayle,  California  Agr.  Expt.  Sta. 

They  feed  on  the  juices  of  leaves  and  fruits  and  cause  russeting 
and  motthng  of  the  fruit.  Often  they  remain  upon  lemons  in 
storage  and  cause  injury  during  the  curing  process. 


Fig.   539. — The   green  lace-wing,   Chrysopa  calif ornica  Coq.,   an  important 
enemy  of  red-spiders.     After  Quayle. 

Control  is  the  same  as  for  the  rust-mite,  the  compounds  of 
sulphur  and  sulphur  in  the  free  state  having  been  found  to  be 
the  best  treatment  for  all  forms  of  mites. 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS  629 

Diabrotica  soror  * 

The  most  common  of  the  leaf-beetles  on  citrus  fruits  on  the 
Pacific  coast  are  the  members  of  this  species  which  is  almost 
identical  with  the  twelve-spotted  cucumber  beetle  or  Southern 
corn-root  worm.  It  attacks  the  tender  foli- 
age of  the  orange  but  rarely  damages  the 
lemon.  The  larva,  like  that  of  the  cu- 
cumber beetles,  feeds  on  the  roots  of  plants 
where  it  is  little  noticed. 

Control.  —  On  small  trees  the  beetles 
may  be  jarred  off  into  tar  or  oil  on  screens 
while  they  are  sluggish  in  the  early  morn- 
ing. On  larger  trees  they  must  be  poi- 
soned.    Lead  arsenate  paste  at   the  rate  F^^-  540.  — Diabrotica 

soror.      After  Quayle, 
of  two   pounds   to   fifty  gallons  water  is      Cal.  Agr.  Exp.  Sta. 

effective.     The  powdered  form,  applied   as  a  dust  with  sulphur, 
might  kill  these  beetles  and  the  mites  at  the  same  time. 

The  Melon  Aphis  f 

The  Melon-aphis  is  occasionally  injurious  to  the  young  shoots 
of  citrus  trees  in  the  spring.  They  are  of  no  special  importance 
to  the  citrus  trees,  but  as  these  serve  as  an  alternate  host  they 
should  be  destroyed  when  present  in  considerable  numbers,  for 
the  protection  of  the  other  host  plants,  such  as  melons,  cotton 
and  other  plants. 

Black-leaf  40,  1  to  1000,  with  soap  as  a  spreader,  is  effective 
here  as  elsewhere. 

The  Orange  Dog  | 

This  conspicuous  caterpillar'  is  the  larva  of  an  equally  con- 
spicuous large,  swallow-tail  butterfly,  black,  with  broad,  yellow 
bands  running  diagonally  across  the  forewings  and  just  inside 
the  margins  of  both  wings. 

The  larva  feeds  on  fohage  but  may  easily  be  destroyed  by  hand- 
picking  or  by  the  use  of  any  arsenical.     This  is  a  Florida  species. 

*  Family  ChrysomelidcF . 

it  Aphis  gossypii  Glover.     See  same,  Chapter  XVIII. 

X  Papilio  cresphontes  Cramer.     Family  Papilionidce. 


630       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 
The  illustration  gives  a  good  idea  of  the  appearance  of  the  larva. 


Fig.  541. — The  orange  dog  caterpillar  on  Xanthoxylon.     Slightly  enlarged. 

The  Southern  Green  Soldier-Bug.* 
This  insect,  also   called  the  pumpkin-bug,  along  with  some 


Fia.  542. — Pumpkin  bug  (Nezara  virdula):  Young.      Six  times  natural  size. 
(From  U.  S.  Bur.  of  Ent.) 

*  Nezara  virdula  Linn.     Family  Pentatomidce. 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS  631 

other  bugs  is  common  on  truck  crops,  clovers  and  other  plants 
and  in  the  fall  when  these  die  and  dry  up  they  sometimes  go  to 
citrus  where  it  attacks  fruit  and  tender  growth,  causing  the 
former  to  drop. 

It  is  similar  in  description  and  habits  to  the  Green  Soldier-bug 
described  as  a  peach  pest.  The  cotton  stainer  (Dysdercus 
suturellus)  is  often  nearly  as  injurious. 

The  adults  go  into  partial  hibernation  during  the  winter 
months.     There  are  several  over-lapping  generations. 

Vontrol. — No  spray  has  been  developed  to  kill  these  bugs  in 
the  adult  stage.  Young  will  be  killed  by  oil,  soap  and  tobacco 
sprays.  Adults  may  be  collected  by  being  jarred  into  large  nets 
held  under  the  trees.     Bugs  so  collected  are  killed  with  kerosene. 

Argentine  Ant.* 

The  Argentine  ant  is  a  household  pest  of  first  importance  in 
certain  regions  and  has  even  greater  importance  in  the  citrus 
groves.  It  is  primarily  of  unportance  in  Louisiana  but  occurs  in 
California  as  well.  It  has  been  known  as  a  household  pest  in 
New  Orleans  for  many  years,  but  was  imported  about  1891, 
presumably  from  the  Argentine,  where  it  was  originally  described, 
on  coffee  ships  running  from  points  in  Brazil  to  New  Orleans. 

Its  chief  importance  in  citriculture  is  its  interference  with  the 
various  species  of  natural  enemies  of  mealy-bugs  and  scale 
insects.  It  is  also  said  to  foster  some  kinds  of  scales  and  plant 
lice  directly  and  to  feed  on  buds,  flowers  and  fruits  of  plants. 
It  is  important  in  the  sugar-plantings  of  Louisiana  where  it 
fosters  a  mealy-bug  (Pseudococous  calceolaricB  Mask.)  which  is 
one  of  the  most  important  enemies  to  sugar-cane  production.  It 
is  said  also  to  interfere  with  the  natural  enemies  of  the  boll 
weevil.  This  makes  a  heavy  indictment  for  one  minute  insect  but 
probably  only  faintly  echoes  the  truth. 

The  Argentine  ant  is  a  very  small  species  of  a  general  brownish 
color.  They  live  in  nests,  usually  in  or  on  the  ground  but  occasion- 
ally in  trees.  Their  destruction  is  usually  a  matter  of  destruction 
of  the  nests,  primarily,  although  it  may  be  possible  to  destroy 
colonies  by  persistent  poisoning  of  the  adults  away  from  the  nests. 

*  Iridomyrmex  humilis  Mayr.  See  J.  R.  Horton  Farmers'  Bulletin,  928 
U.  S.  D.  A.  and  Bulletins  647,  ibid.,  also  WUmon  Newell,  Jour.  Ec.  Ent., 
Vol.  II,  Nos.  2  and  5.     1909. 


632       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  poison  used  to  protect  trees  from  these  ants  in  the  Cali- 
fornia orange  groves  has  been  described  in  the  discussion  of  the 
mealy-bugs.  An  interesting  account  of  methods  of  trapping  and 
of  poisoning  to  rid  orange  groves  in  Louisiana  of  the  ants  will  be 
found  in  the  pubhcation  by  Mr.  Horton  to  which  reference  has 
been  made. 

There  seems  to  be  little  doubt  that,  serious  as  this  insect  is,  it 
can  be  controlled  in  orange  groves  and  in  dwellings,  but  that  it  is 
almost  necessarily  a  problem  for  community  action,  if  permanent 


Fig.   543. — The   Argentine  Ant.      Left,   worker;     Right,   wingless   queen. 
After  Newell.     Jour.  Ec.  Ent. 

results  are  to  be  secured.  Space  here  will  not  permit  further 
discussion  of  the  very  interesting  problems  arising  from  the 
study  of  the  control  of  this  ant. 

Other  Citrus  Insects. 

Some  of  the  most  important  citrus-fruit  insects  do  not  yet 
occur  in  this  country  and  large  sums  of  money  are  spent  annually 
to  keep  them  out  by  maintaining  rigid  quarantines.  They  are, 
therefore,  a  source  of  expense  to  the  industry,  even  though  they 
are  not  actually  present. 

Among  these  there  should  be  mentioned  the  Mexican  Orange 
Maggot   (Trypeta  ludens  Loew.)   and  the  Mediterranean  Fruit 


INSECTS  INJURIOUS  TO  CITRUS  FRUITS 


633 


Fly  (Ceratitis  capitata  Wied.)  and  the  Spring  Citrus  Whiteflj^  or 
the  Black  Fly  (Aleurocanthus  ivoglumi  Ashby). 

The  Black  Fly,  as  the  latter  insect  is  now  generallj'  called,  at- 


FiG.  544. — Fly  of  orange  maggot  (Trypeta  ludens.)  After  Riley, 
tacks  citrus,  mango  and  avocado.  It  came  originally  from  India. 
It  is  a  serious  pest  in  the  Bahamas,  Cuba  and  Jamaica,  but  is  not 
known  in  Florida.  The  State  Plant  Board  of  Florida  is  main- 
taining a  rigid  quarantine  to 
prevent  the  addition  of  this 
very  dangerous  pest  to  the 
list  of  enemies  of  the  citrus 
grower  in  Florida. 

The  orange  maggot  occurs 
in  Mexico  where  it  attacks 
oranges  in  much  the  same 
way  that  the  apple-maggot 
injures  apples,  many  maggots 
being  found  in  the  pulp  of 
the  infested  fruit.  The  Med- 
iterranean fruit  fly  attacks 
oranges  and  also  peaches  and  other  fruits.  It  occurs  in  Ber- 
muda and  Hawaii  and  also  in  all  the  continents  but  the  mainland 
of  North  America.  The  nature  of  its  injury  is  like  that  of  the 
orange  maggot.  The  adults  of  both  species  resemble  the  adults 
of  the   cherry-fruit   fly,  the  currant  fly  and  the  apple-maggot. 


Fig.  545. — Mediterranean  fruit-fly. 
Froggatt. 


After 


634       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Since  citrus  fruits  are,  as  yet,  in  this  country,  free  from  insects 
which  work  within  the  fruit,  no  price  can  be  too  high  to  pay  for 
the  exclusion  of  these  forms. 

The  complete  list  of  the  citrus  insects  from  the  gulf  states  and 
California  is  a  long  one,  but  the  reader  who  is  interested  will  do 
well  to  consult  the  publications  cited  at  the  beginning  of  the 
chapter,  as  well  as  the  bibliography,  for  more  detailed  accounts 
of  the  insects  here  treated  and  for  the  ones  not  mentioned. 


CHAPTER  XXVIII 

INSECTS  INJURIOUS  TO  MAN  AND  TO  THE  HOUSEHOLD. 

Many  insects  attack  man,  directly.  Many  others  injure  him 
indirectly  by  destroying  his  property  within  his  dwellings  or  by 
annojang  him  by  their  presence  even  when  they  are  not  actually 
destructive.  Such  insects  represent  many  groups  of  the  most 
diverse  habits.  The  study  of  some  of  the  more  serious  of  these 
pests  has,  in  comparatively  recent  years,  been  crystallized  into 
the  science  known  as  medical  entomology  and  through  much  of  the 
widely  advertised  work  pertaining  to  certain  forms  the  public  has 
come  to  realize,  as  never  before,  the  importance  of  recognizing 
and  controlling  insects  which  were  formerly  tolerated. 

The  Housefly* 

It  is  certainly  safe  to  say  that  no  insect  is  so  well  known  as  the 

housefly.     It  is  present  in  every  part  of  the  world  inhabited  by 

civilized  man  and  in  most  parts  of  the  world  which  are  capable 

of  sustaining  life  at  all.     While  it  has  always  received  recognition 

as  a  nuisanct  and  a  more  or  less  filthy  and  repulsive  object  it  is 

only  recently  that  it  has  been  recognized  as  an  actual  menace  to 

the  health  of  any  community.     The  feeding  habits  of  the  adult 

render  it  particularly  dangerous  in  the  carrying  of  disease  germs. 

It  feeds  alike  on  foods  prepared  for  the  table  of  man  and  on  the 

vilest  forms  of  animal  waste,  excrement,  sputum,  pus  and  any 

sort  of  decaying  material.     Most  of  these  food  materials  of  the 

fly  are  particularly  adapted  for  the  propagation  of  bacteria  and 

many  of  such  bacteria  are  disease-causing  forms  which  may  be 

infective  when  taken  with  the  food.     It  is  for  this  reason  that  the 

fly  is  particularly  liable  to  be  the  agent  for  the  transmission  of 

typhoid   fever   and   other   diseases   which   affect   the   digestive 

tract.     It  is  also  quite  capable  of   transmitting  tuberculosis  and 

*  Musca  domestica  Linn.  Family  Muscidce.  See  bulletins  from  the 
ir.  S.  Dept.  of  Agr.,  and  the  State  Experiment  Stations.  Titles  too  numerous 
to  be  listed. 

635 


636      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


is  an  object  of  suspicion  in  connection  with  any  infectious 
disease.  The  structure  of  the  adult  fly  and  its  habits  make  it 
more  adaptable  to  the  transmission  of  germ  infections  than 
any  other  insect.  It  has  hairs  and  bristles  on  mouth-parts 
and  feet  which  pick  up  filth  or  other  matter.  Secretions  from  the 
mouth  parts  aid  in  the  infection. 

Possibly  the  greatest  danger  of  infection  from  flies  is  through 
the  milk  supply,  even  though  they  frequent  most  other  foods. 

Milk  is  an  attractive  food  for 
flies  and  is  also  a  very  good 
culture  medium  for  bacteria 
so  that  infection  in  milk  is 
likely  to  develop  more  rapidly 
than  in  other  foods.  And  flies, 
when  they  are  permitted  to 
be,  are  always  more  numerous 
about  dairies  and  meat-mark- 
ets than  elsewhere.  However, 
it  is  not  necessary  here  to  build 
up  a  case  against  the  fly.  The 
foregoing  remarks  will  serve 
merely  as  a  reminder  of  what 
is  already  well-known. 

The  fly  breeds  by  preference 
in  horse  manure  but  will  also 
breed  in  other  kinds  of  man- 
ure, in  many  kinds  of  filth  and 
garbage  and  even  in  human 
excrement.  It  winters  in  the 
larval  and  pupa  stages  and 
There  are  many  overlapping 


Fig.  546. — Housefly  above,  the  stable- 
fly  below,  showing  diff'erence  in 
mouth  parts. 


probably  also  in  the  adult  stage 
generations  in  the  year,  those  late  in  the  season  being  much  larger 
than  ihe  early  ones  because  of  the  heavy  mortality  during  the 
winter  months.  The  adults  need  no  description.  They  are  sim- 
ilar to  the  stable-fly  but  differences  in  their  mouth-parts  illustrated 
in  the  accompanying  figure  will  readily  separate  them. 

It  will  be  seen  that  the  mouth-parts  of  the  housefly  are  such 
that  it  is  unable  to  bite  or  puncture  the  skin.     At  times  the  house- 


INSECTS  INJURIOUS  TO  MAN  AND  IN  HOUSEHOLD      637 


flies  seem  to  be  biting.  This  is  due  to  the  fact,  that  under  some 
weather  conditions  the  stable  flies  seek  shelter  in  the  houses  and 
they,  with  their  piercing  mouth-parts,  do  the  biting  generally 
attributed  to  the  housefly. 

Larvae  of  houseflics  are  white 
maggots  of  the  ordinary  form. 
They  are,  when  grown  about  three- 
eighths  inch  in  length  and  may  be 
found  in  the  breeding  places  men- 
tioned. When  ready  to  pupate 
they  frequently  leave  the  breed- 
ing material  and  travel  some  dis- 
tance in  search  of  suitable  places 
in  which  to  pass  the  pupal  stage. 
This  habit  has  been  utilized  in 
control  measures  as  at  that  time 
they  can  be  trapped.  * 

The  pupae  are  found  in  the  soil 
or  under  rubbish.    They  are  brown, 
regular-oval    objects,     one-fourth    Fig.  547.— Larvae  of  the  housefly. 
inch  in  length  and  will  not  be  readily  distinguished  from  those  of 
several  other  species. 

Control. — Housefly  control  is  accomplished  in  several  ways. 
The  principal  ones  are  abolition  of  breeding  places  and  trapping  of 
adults  and  larvae.  Abolition  of  breeding  places  is  done  by  protect- 
ing all  material  in  which  they  may  breed  by  screening  or  otherwise 

covering  it  until  it  may  be  destroyed. 
Fly-tight  manure  and  garbage  receptacles 
are  widely  used  for  this  purpose.  Gar- 
bages destroyed  as  promptly  as  possible 
and  manure  is  distributed  over  the  fields 
so  that  it  will  dry  out  and  be  no  longer  a 
suitable  breeding  material.  If  the 
screened  receptacles  of  this  type  be  further 
provided  with  flytraps,  so  that  they  will  serve  to  attract  and  cap- 
ture the  adult  flies  which  would  otherwise  have  deposited  their 
eggs  in  them  or  fed  there,  they  will  serve  a  double  purpose. 

*  See  E.  N.  Corv,  Bulletin  213,  Md.  Agr.  Exp.  Sta.  and  R.  H.  Hutchinson, 
Bulletin  200,  U.  S.  Dept.  of  Agr. 


L 


II 


Fig.  548. — Pupae  of  the 
housefly. 


638      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Adult  flies  are  trapped  in  a  great  number  of  different  kinds  of 
traps.     The  principles  of  construction  and  operation  are  so  familar 


Fig.  549. — Hodge  type  window  trap.  At  left  trap  with  end  removed  to  show 
construction.  At  right,  cross  section  of  trap  placed  in  window.  A.  End 
of  trap;  B,  upper  side  of  folds  in  screen;  C,  lower  side  of  folds  in  screen; 

D,  portion  of  end  of  trap  sawed  out  and  returned  after  attaching  screen; 

E,  holes  along  apex  of  folds;  F,  door  for  removing  dead  flies;  G,  window 
sill;  H,  upper  window  sash;  /,  inside  entrance  for  flies;  O,  outside  entrance 
for  flies.     (After  Bishopp,  U.  S.  Dept.  of  Agr.) 

as  not  to  need  description. 
One  is  pictured  below  for 
use  in  windows  of  dwellings 
and  stables,  and  others  for 
different  situations. 

Trapping  of  maggots  is 
based  upon  the  habit  of  mi- 
grating from  the  feeding 
place  just  before  pupating. 
Practical  traps  are  designed 
rather  to  capture  the  larvae 
breeding  in  manure  than 
elsewhere  since  manure  is 
the  only  breeding  material 
that  can  not,  and  should 
not,  be  immediately  de- 
A  shallow  pit  is  dug  and 
Over  this,  about  a 


Fig.  550. — Top  of  garbage  can  with  Hodge 
trap  attached.  (After  Bishopp,  U.  S.  Dept. 
of  Agr.) 

stroyed.     The  construction  is  simple. 

lined  with  cement  so  that  it  will  hold  water. 


INSECTS  INJURIOUS  TO  MAN  AND  IN  HOUSEHOLD      639 


B 


^H 


K 


foot  from  the  bottom,  a  slatted  platform  is  constructed,  the  plat- 
form being  a  little  smaller  in  area  than  the  pit.  On  this  platform 
the  manure  is  stored. 
The  manure  should  be 
kept  wet.  This  may  be 
accomplished  by  pump- 
ing or  sprinkling  water 
over  the  surface  daity. 
This  process  also  keeps 
water  in  the  pit.  When 
the  larvae  migrate  they 
fall  into  the  pit  and  are 
drowned.  Experiments 
have  shown  that  from 
95  to  99  per-cent  of  all 
the  larvae  can  be  de- 
stroyed in  this  way. 
After  about  Um  daj^s  the 
manure  is  no  longer  suit- 
able as  a  breeding  place 
and  it  may  be  removed 
to  make  room  for  more. 
Details    may    be    secured   irom   the   publications   cited. 

Larvae  are  sometimes  poisoned  in  their  breeding  places   by 
treating  the  manure  with  powdered  borax  or  hellebore,  dry  or  in 

water.  About  one  pound  of 
borax  to  16  cubic  feet  is  the 
strength  required,  whileslightly 
less  hellebore  will  give  good 
results.  Careless  handUng  of 
the  borax,  resulting  in  the  un- 
even distribution  or  the  use  of 
too  much  may  result  in  injury 
to  plants  fertihzed  with  the 
manure. 

In  addition  to  the   above 
methods    we  have   the    time 


Fig.  551. — Conical  hoop  fly  trap.    (After  Bish- 
opp,  U.  S.  Dept.  of  Agr.) 


Fig.  552. — One  of  the  green-bottle  flies 
{Lucilia  caesar).  Much  enlarged. 
Howard,  U.  S.  Dept.  of  Agr. 

honored  fly-papers,  fly-killers,  window-screens  and  poisons  for  the 
adult  flies.     These  can,  at  best,  give  only  partial  relief. 


640       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Cleanliness  about  the  house  and  premises  generally  will  result 
in  much  benefit  as  flies  are  attracted  to  dirty  places  by  the  sense 
of  smell. 

Other  flies  are  found  about  the  house.     Among  these,  the 


Fig.  553. — A  "little  house  fly"  (Fannia  brevis):  Female  at  left,  male  at  right 
Much  enlarged.     After  Howard,  U.  S.  Dept.  of  Agr. 

stable-fly  has  been  mentioned.  The  blue  and  green  bottle  flies 
are  well  known  and  are  the  usual  source  of  maggots  in  meat. 
Some  of  the  flesh-flies  also  produce  maggots  in  meat  when  they 


Fig.  554.-The  cluster-fly,  PoHeniarudis   Fig.  555.— The  window-fly,  Scenopt- 
Fab.     After  Howard.  ^^^  fenestralis  L.     After  Howard. 

have  opportunity.     Some  flies  of  other  species  frequent  houses  but 
are  harmless.    A  few  of  these  are  illustrated. 


INSECTS  INJURIOUS  TO  MAN  AND  IN  HOUSEHOLD      641 


Mosquitoes  * 

Mosquitoes,  like  house  flies,  have  long  been  known  as  nuisances, 
almost  intolerable  in  certain  locations,  but  it  is  only  within  the 
last  quarter  of  a  century  that 
their  disease-carrying  possibil- 
ities became  known.  It  has 
been  determined  in  that  time 
that  they  are  the  sole  means 
of  the  transmission  of  malarial 
fever  and  of  yellow  fever  from 
man  to  man,  that  they  trans- 
mit also  certain  tropical  dis- 
eases, and  that  there  are  strong 
probabilities  of  their  being  im- 
plicated in  the  transmission  of 
other  diseases. 
Malarial  fever  is  transmitted 


Fig.  556. — The  house  mosquito;  Culex 
pipiens.  After  J.  B.  Smith,  New  Jer- 
sey Agr.  Expt.  Sta. 

by  mosquitoes  belonging  to  the  genus 
Anopheles,  of  which  there  are  several 
different  species.     It  is  caused   by  a 
minute  one-celled  animal  of  the  lowest 
type,  which  resembles  in  many  ways 
the  bacteria,  but  is  entirely  distinct 
from  them.      This  organism  spends  a 
part  of  its  cycle  of  development  in  the 
body  of  the  mosquito  and  a  part  in  the 
blood  of  man.      Taken  from  man  in 
Fig.  557.-Distinction  be-  ^^e  blood  sucked  up  by  the  mosquito, 
tween  malarial  and  other  it  develops  within  the  body  of  the  mos- 
mosquitoes.   Resting  po-  quito,  then  makes  its  way  to  the  sal- 
sition  of  CmZcx  above  and    .  i       i      r  j^i  -^  i  •     • 

Anopheles  below.    After  ^^ary  glands  of  the  mosquito  and  is  m- 

Howard,  U.  S.  Dept.  of  jected  into  the  blood  of  the  victims  of 

^'  the  mosquito  when  it  bites. 

*  Family  Culicidae.  See  numerous  publications,  those  of  Dr.  J.  B.  Smith, 
from  the  New  Jersey  Exp.  Sta.,  and  of  Dr.  L.  O.  Howard  of  the  Bureau  of 
Entomology,  U.  S.  Dept.  of  Agr.,  being  most  extensive. 


642       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  organism  causing  yellow  fever  is  not  known,  but  it  is  known 
by  absolutely  conclusive  experimental  evidence  which  has  been 
demonstrated  on  a  large  scale,  that  a  mosquito,  (Aedes  calopus)  is 
the  sole  means  of  the  transmission  of  the  disease  from  a  yellow 
fever  patient  to  a  healthy  person.  Soon  after  this  was  proven  it 
was  demonstrated.  The  city  of  Havana  and  the  Panama  Canal 
Zone,  long  centers  of  infection  for  the  fever,  were,  by  a  vigorous 
campaign,  freed  from  mosquitoes.     Yellow  fever,  never  known  to 


Fig.  558. — Dorsal  view  of  the 
larva  of  a  malarial  mosquito, 
Anopheles.    After  Smith,  New 
Jersey  Agr.  Expt.  Sta. 


Fig.    559.  —  The     yellow-fever 
mosquito;  larva.   Much    en- 
larged.    After  Howard,  U.  S. 
Dept.  of  Agr. 


be  absent  in  those  regions,  was  thereafter  almost  unknown.  Other 
cities  have  since  followed  these  examples  and  the  control  of  the 
once  dreaded  disease  is  merely  a  matter  of  thoroughness  in  ridding 
the  locaHties  of  mosquitoes.  Similar  measures  result  in  the 
lessening  or  disappearance  of  malaria. 

Mosquitoes  breed  in  water,  usually  stagnant.  The  larvae  are 
the  common  wrigglers  which  used  to  be  summer  residents  of  every 
rain-barrel.  The  pupae  are  sufficiently  illustrated  in  the  illustra- 
tions, so  they  need  no  description. 

Many  species  of  mosquitoes  are  not  known  to  carry  diseases 
but  are  of  extreme  importance  since,  on  account  of  their  biting 
habits  and  tremendous  numbers,  they  render  large  tracts  of  country 


INSECTS  INJURIOUS  TO  MAN  AND  IN  HOUSEHOLD      643 
almost  uninhabitable  and  in  other  districts,  greatly  reduce  the 


Fig.  560. — A  malaria  mosquito:  a,  eggs;  b,  larva;  c,  pupa;  d,  male  adult; 
e,  female  adult.     After  Howard,  U.  S.  Dept.  of  Agr. 

vitality    of   the   people.      Real   estate   values   in   such    districts 
are,  of  course,  far  below  the  normal.     Two    important    species, 


Fig.    561. — The    yellow-fever    mosquito;    adult    female,    side    view.     Much 
enlarged.     After  Howard,  U.  S.  Dept.  of  Agr. 


644       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


both  of  which  we  illustrate,  are   the    House    Mosquito  (Culex 
pipiens),  and  the  Salt-Marsh  Mosquito  (Culex  sollicitans). 

Mosquito  control  is  based  upon  the  breeding  habits.     Eggs, 


Fig.  562.— The  yellow-fever 
mosquito:  pupa.  Much  en- 
larged. After  Howard,  U. 
S.  Dept.  of  Agr. 


Fig.  563. — Culex  pupa.  After 
L.  O.  Howard,  U.  S.  Dept. 
of  Agr. 


larvae  and  pupae  are  found  in  the  water.  If  stagnant  water  is 
removed  from  a  locality  the  mosquitoes  will  go.  If  it  is  removed 
in  part,  the  mosquito  plague  will  be  lessened.  If  it  is  rendered 
unfit  for  the  mosquito  in  any  way  the  effect  will  be  the  same. 
Control  measures,  therefore,  in- 
clude drainage  of  swamps,  ponds, 
pools  and  other  standing  water 
where  possible ;  the  oihng  of  stand- 
ing water  that  can  not  be  drained 
away,  since  a  film  of  oil  on  the 
surface  of  the  water  destroys 
all  stages  of  the  mosquitoes  in 
the  water  and  effectively  prevents 
breeding  so  long  as  it  remains; 
treating  water  with  chemicals  to 
destroy  young  of  the  mosquito; 
stocking  sluggish  streams  and  artificial  lakes  with  species  of  fish 
which  feed  on  mosquito  larvae  and  pupae.  Of  these  the  most 
effective  method  is  drainage.  To  be  thoroughly  effective  it  must 
take  into  account  not  only  large  bodies  of  water  but  also  the  water 
which  may  stand  in  sewers,  old  cans  in  a  back  yard,  stopped-up 


Fig.  564. — A  mosquito  egg-boat  and 
larvae  just  hatched  (Cwiex).  From 
Howard,  U.  S.  Dept.  of  Agr 


INSECTS  INJURIOUS  TO  MAN  AND  IN  HOUSEHOLD        645 


drain-pipes  on  houses  and,  in  fact,   any  standing  water  which 

will  remain  for  as  much  as  a 
week.  It  is  usually  necessary  to 
supplement  drainage  with  oiling. 
In  several  states  expensive 
drainage  operations  have  re- 
claimed thousands  of  acres  of 
land  which  was  useless.  These 
operations  are  usually  under 
state  direction  and  at  state  ex- 
pense, at  least  in  part. 

The  use  of  chemicals  in  the 
water  is  still  in  the  experi- 
mental stage. 

Mosquitoes,  in  the  north,  usu- 
ally winter  as  adults.  There  are 
several  generations  in  a  season,  a 
generation    requiring  in    warm 

_  ^  ,  „.  .  ,,,       weather  less  than  two  weeks  and 

Fig.     565. — Culex     sollicitans.    (After   .  ,  ^,  ,     , 

Smith,  Report  on  Mosquitoes  of  New  m     cooler   weather    somewhat 

Jersey).  longer. 

The  accompanying  illustrations  will  take  the  place  of  descriptions. 

Fleas  * 

The  flea  is  a  third  insect  which  has,  within  the  very  recent  past 
been  transferred  from  the  list  of  innocuous  pests  and  placed 
with  the  dangerous  insect  enemies  of  man.  While  it  is  true  that 
some  common  species  have  not  yet  been  proven  to  be  specific 
bearers  of  disease  it  is  now  known  that  one,  the  rat-flea 
(Xenopsylla  cheopsis)  has  been  pretty  definitely  proven  to  be  the 
usual,  if  not  the  only,  means  of  transmission  of  the  plague  or 
bubonic  fever.  This  fact  puts  all  fleas  under  suspicion  and  makes 
them  even  less  tolerable  under  civilized  conditions  than  before. 

Fleas  that  affect  man,  in  the  more  enlightened  portions  of  the 
world,  are  more  or  less  accidental  visitors  from  domestic  animals, 
usually  cats  and  dogs.  There  are  several  species,  the  more 
important  being  the  human  flea  (Pulex  irritans).  and  the  cat  and 

*  Order  Siphonaptera. 


646       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

dog-flea,  (Ctenocephaliis  canis).  These  breed  in  accumulations  of 
organic  matter  in  protected  places  where  there  is  some  moisture. 
This  may  be  in  cracks  and  crevices  in  the  floor  of  a  dwelling,  in 
dirt  floors  of  basement  rooms,  or  in  the  soil  under  buildings  where 
the  animals  are  allowed  to  go.  The  larvae  are  like  slender  maggots 
and  are  rather  inactive.  The  length  of  the  life  cycle  is  quite 
variable,  ranging  from  less  than  three  weeks  to  several  months. 
Adult  fleas  attack  animals  of  many  kinds,  including  man.     Some 


Fig,  566. — ^The  dog  flea:  a,  egg;  b,  larva  in  cocoon;  c,  pupa;  d,  adult;  b,  c,  d, 
much  enlarged;  a,  more  enlarged.     U.  S.  Dept.  of  Agr. 

forms  attack  poultry  and  one  of  the  most  important  members  of 
the  group  is  the  chicken  sticktight  flea,  discussed  later. 

Domestic  fleas  are  controlled  by  killing  the  adults  and  by 
eliminating  breeding  places.  They  may  be  killed  on  animals  by 
the  use  of  some  of  the  insecticide  soaps,  of  which  there  are  many 
on  the  market,  or  by  the  use  of  some  stock-dip  composed 
of  the  coal-tar  derivatives  such  as  creolin,  in  water.  All  the  fleas 
must  be  thoroughly  wet  with  the  mixture.  Kerosene  emulsion 
at  a  strength  of  about  one  to  fifteen  may  be  substituted,  care 
being  taken  to  have  the  oil  all  emulsified.     Napthalene  powder 


INECTS  INJURIOUS  TO  MAN  AND  IN  HOUSEHOLD      647 


dusted  into  the  hair  will  cause  the  fleas  to  drop  off.  If  the  animal 
be  held  over  white  paper  the  stupefied  fleas  falling  on  the  paper 
can  easil}^  be  caught  and  killed. 

Fleas  in  breeding  places  may  be  killed  by  treating  with 
gasoline  or  kerosene,  if  where  such  substances  can  be  used  safely. 
Under  permanent  carpets  the  only  remedy  is  to  remove  and 
thoroughly  clean  the  carpets 
and  to  treat  the  floors  with 
strong  soapsuds  or  gasoline. 
Movable  rugs  are  much  better 
from  the  standpoint  of  flea 
control  than  carpets.  It  is 
probable  that  where  a  vacuum 
cleaner  is  used  frequently  little 
trouble  will  be  experienced 
with  fleas.  When  fleas  are 
breeding  out  of  doors  all  the 
rubbish  should  be  cleaned  off 
the  ground  and  the  soil  soaked 
with  salt  water. 

Control  of  the  rat  flea  in- 
volves destruction  of  rats  and 
this  is  done  in  cities  as  a  community  proposition.  In  seaports 
such  as  San  Francisco  and  New  Orleans,  where  bubonic  plague 
sometimes  appears  this  is  more  important  than  elsewhere.  At  the 
same  time  modern  civilization  has  proscribed  the  rat  and  it 
should  be  destroyed  for  other  reasons. 

Further  details  in  the  treatment  of  fleas  may  be  obtained  from 
Farmers'  Bulletin  897,  U.  S.  Department  of  Agriculture,  "Fleas 
and  Their  Control,"  by  F.  C.  Bishopp. 

Bedbugs  * 

The  bedbug  has  not  yet  been  proven  guilty  of  transmitting 
any  definite  disease  of  importance  in  this  country.  It  is  under 
suspicion  because  its  habits  give  it  the  opportunity  to  carry  many 
different  kinds  of  disease.  This  it  undoubtedly  does,  in  the  role 
of  a  simple  carrier,  if  not  as  a  direct  inoculator. 

The  bedbug  is  a  small,  flattened,  brownish  insect  which  may 
*  Cimex  lectularius,  Linn.     Family  Cimicidce  (AcanthiidcB) . 


Fig.  567. — The  human  flea:  adult  male. 
Greatly  enlarged.  After  Bishopp  U. 
S.  Dept.  of  Agr. 


648       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


reach  the.  length  of  one  fourth  inch.  It  hves  in  the  habitations  of 
man,  especially  in  old  or  poorly  kept  houses  where  it  has  plenty 
of  cracks  and  crevices  in  which  to  hide  or  where  it  is  little  disturbed 
by  the  housekeeping  process.  The  eggs  are  deposited  in  secluded 
places  and  the  young  resemble  the  adults.  They  feed  to  some 
extent  on  mice  and  on  domestic  animals  and  in  addition  can 
exist  for  long  periods  without  food  as  they  are  often  found  in 
houses  which  have  been  vacant  for  months. 

Control  is  a  matter  of  eliminating  all  hiding  places  possible 
and  treating  the  others  with  benzine,  kerosene,  carbolic  acid  or 


Fig.  568. — Bedbug:  a,  and  h,  adult  females  from  above  and  below,  gorged 
blood;  c,  and  d,  structural  details.  (After  Marlatt,  U.  S.  Dept.  of  Agr., 
Ent.  Bui.  4,  n.  s.  1896.) 

other  substances  and  repeating  the  treatment  until  all  signs  of  the 
bugs  disappear.  Fumigation  and  heating,  to  120°  or  higher  are 
effective  when  practical. 

Lice  * 

Lice  are  the  most  disgusting  of  the  human  parasites  and  are 
no  longer  common  among  enlightened  peoples  except  in  situa- 
tions where  the  ordinary  sanitary  precautions  can  not  be  observed 
The  louse,  or  "cootie"  of  the  armies  in  the  war  is  an  example 
of  extraordinary  development  of  a  species  under  unusual  con- 

*  Pediculidce.     Order  Siphunculata. 


INSECTS  INJURIOUS  TO  MAN  AND  IN  HOUSEHOLD     649 

ditions.  Lice  are  more  commonly  found  in  camps  and  among 
children  in  poor  surroundings. 

There  are  three  common  species:  The  head-louse  (PedicuUs 
capitis),  the  body-louse  (Pediculus  vestmenti),  and  the  pubic 
louse  (Phthirius  inguinalis) 

The  body  louse  is  the  ''cootie"  of  the  "A.  E.  F."  or  the  "gray- 
back"  of  the  lumber  camps.  It  attaches  itself  to  clorhing,  con- 
ceahng  itself  in  seams  where  the  eggs  are  laid.  From  there  it  makes 
its  way  to  the  body  only  to  feed.  The  head  louse  spends  its  entire 
life  in  the  hair  on  the  head,  attaching  its  eggs  or  "nits"  to  the 
hairs. 

Head  lice  may  be  killed  l)y  the  use  of  hair-oils  or  other  oil 
which  will  not  injure  the  hair  or  skin.  Clipping  the  hair  is  the 
best  remedy  for  children.  Body  lice  require  treatment  of  the 
body  and  of  the  clothing.  Clothing  should  be  steamed  or  fumi- 
gated and  underclothing  boiled.  Oils  or  sulphur  ointment  or 
"blue  ointment"  will  kill  the  lice  on  the  body.  Oils  were  very 
largely  used  in  the  "de-lousing  stations"  among  the  allied  armies 
in  France.  A  very  effective  remedy  is  to  sponge  the  entire  body 
with  a  solution  of  bi-chloride  of  mercury,  1  to  1000,  washing  the 
body  a  few  minutes  later.  This  will  kill  all  stages  in  one  thorough 
application.  It  is  applicable  for  all  species  but  is  not  so  desirable 
for  use  on  the  head  louse. 

Chiggers  * 

These  pests  will  need  little  description  for  those  readers  who 
live  in  the  South  and  the  Central  States,  at  least  the  effect  of 
them  will  be  familiar  to  all  in  those  regions  where  they  are  the 
bane  of  the  barefoot  youngsters  on  the  farm  and  are  at  times 
troublesome  to  adults.  They  are  minute  mites,  probably  of 
different  species,  which  live  normally  on  certain  weeds  and  are 
especially  abundant  in  berry  plantings  or  among  wild  berry 
vines.  When  they  are  jarred  off  onto  the  skin  they  immediately 
burrow  and  later  become  engorged  with  blood,  causing  intense 
itching  and  local  swellings.  This  feeding  habit  is  not  normal  for 
them  and  the  mites  die,  but  only  after  the  damage  is  done. 

*  Order  Acarina,  Class  Arachnida. 


650       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Susceptible  persons  should  avoid  places  where  the  mites  or 
chiggers  are  known  to  be  numerous  or,  if  compelled  to  visit  such 
places  may  prevent  ill  effects  by  bathing  in  strong  soapy  water 
to  which  some  salt  has  been  added.  If  this  is  done  within  a 
few  hours,  no  inconvenience  will  be  noticed.  After  the  injury 
has  appeared,  the  irritation  may  be  allayed  by  use  of  ammonia 
or  soda.  Sulphur  dusted  into  the  clothes  will  prevent  attack 
by  the  mites. 

The  season  for  the  mites  is  mid-summer  to  early  autumn. 


Fig.  569. — Common  "  Chiggers  ".  Leptus  americanus  at  left ;  Leptus  irritans 
at  right.  Highly  magnified,  dots  under  anal  extremity  indicating  natural 
size.     (After  Riley),  U.  S.  Dept.  of  Agr. 

Roaches  * 

The  roaches  which  infest  the  house  are  of  several  kinds,  but 
all  are  alike  in  their  habits  and  similar  in  their  mode  of  develop- 
ment. They  injure  food  not  so  much  by  feeding  upon  it,  although 
they  will  eat  almost  anything,  as  by  running  over  it  and  making 
it  unfit  for  human  consumption. 

Roaches  hide  during  the  daytime  in  cracks  and  crevices,  under 
floors,  behind  baseboards,  around  water  pipes  and  wherever  they 
can  escape  observation.  In  these  places  they  lay  their  eggs, 
which  are  produced  in  relatively  large,  bean-shaped  capsules 
which  are  carried  for  some  time  projecting  from  the  abdomen 
of  the  females.  The  young  develop  slowly,  months  being  some- 
times required  and  often  the  eggs  do  not  hatch  for  long  periods. 

*  Family  Blattidos. 


INSECTS  INJURIOUS  TO  MAN  AND  IN  HOUSEHOLD     651 


For  this  reason  control  measures  must  be  kept  up  persistently  so 
as  to  kill  newly  haiched  young  as  they  appear  from  time  to  time 
Roaches  may  be  killed  with  poisons  or  by  fumigating  or  they 
may  be  trapped.  A  trap  described  by  Mr.  C.  L.  Marlatt,  of 
the  Bureau  of  Entomology,  is  the  acme  of  simplicity.     It  consists 


Fig.  570. — The  German  roach  (Blattella  germanica):  a,  first  stage;  6,  second 
stage;  c,  third  stage;  d,  fourth  stage;  e,  adidt;  f,  adult  female  with  egg 
case;  g,  egg  case,  enlarged;  h,  adult  with  wings  spread.  All  natural 
size  except  g.     (From  Riley,  U.  S.  Dept.  of  Agr.) 

of  an  ordinary  breadpan  with  the  sides  greased  with  rancid 
butter.  The  butter  acts  as  a  bait  and  the  roaches  fall  into  the 
pan  and  are  unable  to  climb  up  the  greased  sides  and  escape. 


{^W) 


Fig.  571. — The  American  roach  {Periplaneta  americana) :  a,  view  from  above; 
6,  from  beneath.  Both  enlarged  one-third.  After  Marlatt,  U.  S.  Dept. 
of  Agr. 

Roaches  may   be   poisoned   with    chocolate   mixed   with   borax, 

about  equal  parts  being  used.     Plaster  of  paris  mixed  with  flour 

or  with  chocolate  has  also  been  recommended.    Sodium  fluoride 


652        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

is  the  best  standard  poison  and  repellant.  If  this  be  dusted  ia 
all  cracks  and  hiding  places  every  few  days  and  the  treatment 
be  kept  up  for  several  weeks,  the  roaches  will  be  entirely  killed 
or  driven  away.  All  control  measures  available  should  be  put 
into  use  at  the  very  first  sign  of  roaches  on  the  premises.  If  this 
is  done  no  heavy  infestation  can  occur. 

The  common  roaches  belong  to  four  species.  The  Oriental 
Cockroach  (Blatta  orientalis  L.)  is  of  European  or  Asiatic  origin. 
The  German  Roach  {Blatella  germanica  L .) ,  was  also  introduced 
from  Europe  while  the  Australian  Roach  (Periplaneta  australasicB 
Fabr.),  comes  to  us  from  Australia.  The  fourth  species  is  the 
American  Roach  {Periplaneta  americana  L.),  the  largest  species 
and  a  native  one.  No  essential  difference  in  their  habits  is  to 
be  noted. 

House  Ants  * 

Ants  of  several  species  have  been  troublesome  pests  of  man 
as  far  back  as  history  gives  any  records.     They  destroy  food  and 
render  it  unfit  for  use  and  at  times  actu- 
ally   attack    man.      There    are   several 
species. 

The   Little  Red  Ant,    (Monomorium 

pharaonis  Linn.,)  is  the  smallest  species 

and   perhaps   the   worst.    It  makes   its 

nests   under   houses    or   in    the    ground 

nearby  and  is  often  difficult  to   get   at. 

The  Little  Black  Ant,   {Monomorium 

minimum  Buckley,)  is  larger  and  darker 

in  color,  being  about  three-sixteenths  of 

Fig.  572.— The  Little  Red   an    inch   in   length   while    the    previous 

Ant.    From  Riley.  species  is  not  more  than  half  that  length. 

The  black   form   generally  makes   its   nests   outside   the  house 

where  they  are  more  readily  accessible. 

The  Argentine  Ant  (see  page  631),  has  already  been  discussed. 
It  is  the  most  serious  pest  among  the  ants  where  it  occurs. 

The   Black  Pavement  Ant,  {T etramoriwm  ccBspitum  Linn.,)  is 
much  larger  than  the  others,  some  individuals  being  nearly  one- 
half  inch  long.     It  is  frequently  found  in  houses  but  is  never  as 
numerous  as  the  smaller  species. 
*  Family  Formicidce. 


INSECTS  INJURIOUS  TO  MAN  AND  IN  HOUSEHOLD       653 


Ants  may  be  controlled  by  exposing  poisoned  syrup,  made 
according  to  the  directions  given  on  page  G08,  where  they  can 
have  easy  access  to  it.  The  writer  has  tried  this  many  times  for 
different  ants  and  they  have  invariably  disappeared  in  a  short 
time.  This  has  been  so  satisfactory  that  it  seems  unnecessary 
to  suggest  anything  else. 

The  Carpet  Beetle  * 

The  Carpet  Beetle,  the  larva  of  which  is  commonly  called  the 
"Buffalo-Moth,"  injures  carpets  and  other  animal  products  or 
fabrics.  The  adult  is  a  small  beetle  one-eighth  inch  in  length,  of 
oval  shape  and  dark  or  black  color  with  lighter  markings  giving  it  a 


Fig.  573.— The  Carpet  Beetle.     From  Riley. 

mottled  effect.  The  larvae  are  thick,  soft-bodied,  hairy  grubs 
found  in  and  about  the  food  materials.  Eggs  are  laid  on  the  food 
and  eggs,  larvae  and  pupae  will  be  found  in  or  near  the  food  while 
the  adults  leave  the  houses  and  fly  to  flowers  at  times. 

A  similar  species,  darker  in  color  and  without  the  light  markings, 
is  the  Black  Carpet  Beetle  (Attagenus  piceus  Oliv.). 

Control  measures  consist  in  taking  up  carpets  and  rugs  and 
beating  and  airing  them.  Thorough  sweeping  of  the  floors 
followed  by  treatment  of  the  cracks  with  gasoline  will  kill  the 
young  which  may  be  present.  Fumigation  or  heating  will  be 
found  to  be  effective.  The  substitution  of  rugs  for  carpets  is 
advised.  Where  this  is  not  desirable  protection  for  the  carpets 
can  be  secured  by  placing  building  paper  under  them  and  dusting 

*  Anthrenus  scrophularice  L.,  Family  Dermestidw. 


654        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


or  sprinkling  the  paper  with  alum,  powdered  or  in  solution.  If 
the  paper  is  not  used  the  same  protection  will  be  secured  by- 
dusting  powdered  alum  under  the  carpets.  A  vacuum  cleaner 
is  very  effective  in  keeping  out  these  insects. 

The  Clothes  Moths  * 

The  clothes  moths  are  among  the  most  annoying  of  household 
pests  and  the  injury  they  do  is  considerable.  They  feed  on  woolens, 
feathers  and  fur  and  more  rarely  on  other  fabrics.  There  are 
three  species,  the  Case-Making  Moth  {Tinea  pelionella  L.), 
being  the  most  common  while  the  Webbing  Clothes-Moth  (Tinea 
hiselUella  Hummel),  is  common  in  some  more  southern  localities 


Fig.  574. — A  clothes  moth  (Tinea  pellionella).     From  Riley. 

and  a  third,  the  Tapestry  Moth  (Tricophaga  tapetzella  L.),  is 
rather  rare  and  much  larger  and  more  striking  in  color  than  the 
commoner  species.  The  common  forms  are  minute  yellowish- 
white  moths  with  faint  darker  markings.  One  species  makes 
for  itself  small  tube-like  cases  of  the  material  upon  which  it  is 
feeding  and  silk  spun  by  itself.  The  other  spins  webs  throughout 
its  galleries  but  does  not  make  cases.  The  larvae  are  very  small 
whitish  caterpillars.  The  case-making  moth  has  but  one  genera- 
tion appearing  in  the  spring  while  the  other  common  species  has  a 
fall  generation  as  well. 

Small  quantities  of  clothing  may  easily  be  protected  by  fumigat- 
ing them  in  a  trunk  with  carbon  bisulphide,  observing  the  usual 
precautions.     They   may    also   be   fumigated   in    a   good   tight 
clothes-closet,     preferably    in    an    unused    room.     Moth    proof 
*Famly  Tineidce. 


INSECTS  INJURIOUS  TO  MAN  AND  IN  HOUSEHOLD      655 


bags  for  the  storage  of  woolen  articles  are  of  value.  Cold  storage 
is  one  of  the  safest  forms  of  protection  through  the  summer 
months.  Any  box  which  can  be  made  practically  air-tight  will 
afford  protection  if  the  articles  are  uninfested  when  the  boxes  are 
closed. 

We  have  found  that  storing  in  rooms  where  the  temperature 
is  uniformly  high,  above  90  at  all  times,  will  afford  as  complete 
protection  as  the  cold  storage. 

Miscellaneous  Household  Insects 
The  Silverfish  or  Fish-Moth  {Lepisma  saccharalis  or  domesiica) 

is  an  insect  which  sometimes  defaces  papers  or  gets  into  food 

materials   but    is   not   usually  serious.' 

The  general  belief  is  that  they  feed  on 

starchy  materials  by  preference  but  will 

feed  on  animal  matter. 

The    House    Centipede     (Scutigera 

forceps),  not  an  insect  at  all  but  a  cen- 
tipede, is  a  slender-bodied  animal  with 

many  very  long  legs    frequently    seen 

running  on  walls  and  ceilings.      It  is 

not  injurious,  except  to  delicate  nerves, 

as  it  feeds  upon  flies  and  other  insects. 
Book-hce  (Corrodentia),  are  minute 

louse-like  insects,  almost  colorless  and^ 

just   large   enough   to   be   seen,  which 

run   over   old   books   and   papers   and 

sometimes   may   deface  them  slightly. 

They,  however,  do  httle  damage  and 

need  not  be  feared.  ^■Jboft't^oS  o^'eXu^l; 

White  ants  or  Termites  (Leucotermes  times  natural  size  (Marlatt, 
flavipes),  are  ant-like  insects  which  U.  S.  Dept.  of  Agr.) 
sometimes  do  considerable  injury  by  mining  into  the  foundation 
timbers,  floors  and  even  walls  of  houses.  They  have  been  known 
to  cause  the  collapse  of  large  buildings  and  often  necessitate 
replacing  foundations  and  floors  in  the  southern  states.  They 
injure  plants  also,  injury  having  been  noted  on  the  orange,  on 
plum    and    particularly    on    apple-seedhngs  in  the  middle-west. 


656       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

They  live,  like  true  ants,  in  colonies  and  have  different  kinds 
of  individuals  or  castes. 

Except  for  the  black,  winged  males  and  females  which  may  be 
seen  emerging  and  flying  from  the  nests  for  a  few  days  in  the 


Fig.  576. — The  house  centi-  Fia.577. — Adult  book-louse,  about 
pede     {Scutigera  forceps):  fifty  times  natural  size    (After 

Adult.  Natural  size.  (After  Back,   U.   S.   Dept.   of  Agr.) 

Marlatt,  U.S.  Dept.  of  Agr.) 

spring,  they  are  soft-bodied,  yellowish-white,  wingless  insects 
about  one-fourth  inch  long.  They  normally  live  in  decaying 
wood  out  of  doors. 

Control  consists  largely  of  prevention.  Where  they  are 
prevalent  it  is  well  to  use  concrete  for  foundations  or  to  treat 
timber  to  be  used  with  creosote  preparations  of  some  kind. 

The  insects  injurious  to  stored  grains  infest  also  many  stored 
food  products.  For  a  complete  discussion  of  these  the  reader  is 
referred  to  Chapter  X. 


CHAPTER  XXIX. 
INSECTS  INJURIOUS  TO  DOMESTIC  ANIMALS  AND  POULTRY 
Several  of  the  insects  listed  as  pests  of  man  are  also  annoying 
or  injurious  to  domestic  animals.  Among  these  the  most  import- 
ant are  the  mosquitoes.  House  flies,  although  present  in  large 
number  where  there  are  animals,  do  not  cause  injury  of  a  direct 
nature  and  do  not  annoy  the  animals  particularly  since  they  are 
unable  to  bite. 

The  Stable  Fly* 

The  stable  fly  resembles  very  closely  the  house  fly,  the  most  easily 
noticeable  difference  being  in  the  mouth  parts,  as  shown  in  Fig.  546. 

The  habits  of  the  stable  fly  are  quite  similar  to  those  of  the 
house  fly  also.  The  eggs  are  laid  on  straw  or  other  material  and 
the  larvae  develop  on  decaying  vegetation  of  many  kinds,  usually 
in  manure  which  contains  a  large  amount  of  straw  or  in  scattered 
or  wet  and  decaying  straw  from  the  bottoms  of  stacks. 

The  adults  bite,  attacking  many  domestic  animals,  and  are 
frequently  the  most  annojdng 
and  numerous  of  the  flies  to 
be  found  on  animals,  usually 
being  so  in  stables. 

Stable  fly  control  is  se- 
cured in  the  same  way  as 
house  fly  control,  by  eliminat- 
ing,  so  far   as  possible,  the 

breeding  places  and  by  trap-   Fig    578.— The  stable  fly :  Adult  female, 

,  ,   .      r,-  m.,  Side  view,engorgea  With  blood.  Greatly 

pmg    the   adult   flies.       The       enlarged.     (After  Bishopp,  U.  S.  Dept. 

same  means    to    accomplish       °^  -^sr-) 

these  ends  are  used  as  in  case  of  the  house  fly,  taking  into  account 
the  slight  differences  in  the  breeding  places.  A  fly  eradication  cam- 
paign should  make  no  difference  in  the  species  but  destroy  all  flies 
possible.  Control  measures  may  be  supplemented  by  protection 
of  animals.     This  may  be  done  by  screening  windows  of  stables 

*  Stomoxys  calcitrans  L.     Family  Musddce.     See  F.  C.  Bishopp,  Farmers' 
Bulletin  540. 

657 


658       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


or  by  darkening  the  stables.  It  is  accomplished  to  some  extent 
by  the  use  of  fly  nets,  most  of  which  are  of  little  use,  or  other 
covers  for  the  animals.  It  is  also  accomplished  by  the  use  of 
repellant  substances  sprayed  on  the  animals,  but  this  process 
usually  affords  only  temporary  relief  and  is  troublesome  and 
expensive.  Proper  care  of  straw  to  prevent  its  becoming  scattered, 
wet  and  rotten,  will  prevent  breeding  to  a  large  extent.  On  the 
whole,  the  best  control  will  be  secured  by  the  use  of  fly-traps  in 
the  stable  windows  and  the  disposal  of  such  wastes  as  may  furnish 
breeding  places  as  promptly  as  conditions  permit. 

The  Horn  Fly  * 

In  appearance  the  horn  fly  is  very  much  like  a  small  house  fly 
but  its  mouth  parts  are  similar  to  those  of  the  stable  fly  and  are 


Fig.  579. — The  Horn  fly:  a,  egg;  6,  larva;  c,  pupa;  d,  adult. 
U.  S.  Dept.  of  Agr.) 


(After  Marlatt, 


used  to  good  effect  to  the  same  purpose.  It  attacks  cattle  for  the 
most  part  and  is  found  clustered  in  large  numbers  about  the  horns, 
on  the  shoulders  and  flanks  of  cattle  in  pasture  all  through  the 
summer.  It  is  possibly  the  most  annoying  of  the  flies,  attacking 
cattle,  and  is  certainly  responsible  for  loss  of  weight  and  reduction 
in  the  milk  flow  so  noticeable  in  the  fly  season. 
*  Haematobia  serrata  R.-D.     Family  Miiscidae. 


INSECTS  INJURIOUS  TO  DOMESTIC  ANIMALS,  Etc.      659 


The  horn  fly  was  brought  from  Europe  some  fifty  years  ago 
and  has  spread  over  the  greater  part  of  this  country.  It  is  more 
difficult  to  suggest  control  measures  for  it  than  for  the  other  species 
since  it  breeds  in  the  droppings  from  animals  in  the  pastures.  If 
these  can  be  spread  out  so  that  they  will  dry  quickly,  no  flies  can 
develop,  but  it  is  seldom  that  conditions  will  permit  this.  Shelter- 
ing cattle  during  the  heat  of  the  day  and  providing  plenty  of  shade 
and  water  in  the  pastures  will  alleviate  the  discomfort  of  the 
animals.  Provide  brush  patches  through  which  the  cattle  may 
pass  to  brush  off  flies  that  they  can  remove  in  no  other  way. 
Eepellents,  as  for  the  stable  fly,  while  they  may  be  somewhat 
effective  will  rarely  be  practical. 

Horse  Flies  * 
Several  kinds  of  flies,  ranging  in  size  from  that  of  the  house  fly 


^ 

'J 

y 

ik 

',-  ,     _j 

....       '  ,.,-i 

Fig.  580.— The  Black  Horse  Fly.     (After  Carman,  Ky.  Agr.  Exp.  Sta.) 

to  more  than  an  inch  in  length  are  common  pests  of  horses  and 
cattle  and,  upon  occasion,  attack  man.     The  more  famihar  kinds 
*  Family  Tahanidoe. 


660       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

are  the  large  Black  Horse  Fly  (Tabanus  atratus  Fab.),  which  is, 
the  largest  form  commonly  seen  and  particularly  abundant  in 
wooded  sections  where  its  vicious  biting  and  bullet-like  flight 
make  it  quite  conspicuous ;  a  slightly  smaller  grayish-brown  some- 
what striped  species  is  nearly  as  large  and  is  found  on  cattle  more 
frequently  than  is  the  preceding;  and  the  several  smaller  kinds 
with  green  eyes,  suggesting  the  common  name  Greenheads, 
{Tabanus  lineola  Fab.  is  one),  which  attack  by  preference  the  ears 
of  horses  and  do  not  hesitate  to  attack  man. 

Larvae  of  horse  flies  are  cylindrical  maggots,  pointed  at  both 
ends,  which  live  in  ponds  and  marshes. 

Little  can  be  done  to  eliminate  the  horse  flies,  or  gad-flies  as  they 
are  sometimes  called.  Fly-nets,  with  ear-nets  attached  are  much 
more  useful  for  these  than  for  the  smaller  flies  which  attack  animals. 

The  Screw  Worm  Fly  * 

In  the  southwest  an  important  insect  pest  of  livestock,  par- 
ticularly range  animals,  is  a  maggot  or  screw-worm,  the  larva  of  a 
fly  intermediate  in  size  and  appearance  between  the  common  house 
and  stable  flies  and  the  green-bottle  flies.  The  distribution  of  the 
insect  includes  the  territory  from  the  lakes  to  the  gulf,  but  it  is  a 
serious  problem  only  in  the  South  and  Southwest. 

The  injury  is  the  result  of  the  work  of  the  larvae  in  the  flesh  of 
the  infested  animals.  Eggs  are  deposited  by  the  adults  in  wounds 
or  often  even  on  exposed  mucous  membranes.  The  larvae  upon 
hatching  burrow  in  the  flesh  and  cause  inflammation  and  mechanical 
injury  followed  by  infection  and  the  sores  refuse  to  heal  without 
treatment.  Wire-cut  animals,  saddle-galled  horses,  and  range 
cattle  at  the  time  of  calving,  offer  conditions  suitable  to  attract 
these  flies.  Injury  to  man  is  not  uncommon,  the  eggs  being  usually 
deposited  in  the  nostrils  during  sleep  and  the  larvae  working  their 
way  up  into  the  nasal  passages.  Children  are  the  most  frequent 
sufferers. 

The  extent  of  the  injury  in  the  infested  regions  is  hard  to  esti- 
mate but  it  is  certainly  great.  The  flies  breed  in  decaying  animal 
matter  as  a  rule,  the  infestation  of  living  animals  being  only  an 
occasional  habit  for  the  species. 

*  Chrysoniyia  macellaria  Fabr.  Family  Muscidce.  See  Bishopp,  Mitchell 
and  Parman,  Farmers'  Bulletin  857,  U.  S.  Dept.  of  Agr. 


INSECTS  INJURIOUS  TO  DOMESTIC  ANIMALS,  Etc.        661 

Control  is  difficult,  but  partial  control  at  least  is  not  impossible. 
Since  the  great  majority  of  the  flies  mature  in  carcasses  of  dead 
animals  the  proper  disposal  of  these  is  of  greatest  importance. 
Burning  is  the  approved  method.  If  this  can  not  be  done  they 
should  be  buried.  If  they  can  be  covered  with  lime  before  the  soil 
is  thrown  on  them  it  will  give  better  results.  Elimination  of 
points  of  infestation  by  prevention  of  wounds,  destruction  of  ticks, 
since  the  tick  wounds  are  points  of  entrance  into  the  animals,  and 
the  arrangement  of  the  calving  season  so  that  the  calves  will  be 
produced  when  the  flies  are  not  present,  will  lessen  the  losses. 

Treatment  of  wounds  already  infested  involves  the  use  of 
chloroform  to  kill  the  maggots  and  the  use  of  a  good  repellent 
substance  on  the  wounds  to  keep  away  flies.  Pine  tar  is  recom- 
mended as  a  satisfactory  repellent. 

Maggots  from  several  other  species  of  flies  sometimes  are  found 
in  wounds  but  they  exhibit  a  preference  for  wounds  showing 
infection  and  having  some  morbid  flesh  in  them.  Most  any  of  the 
meat-infesting  maggots  may  be  found  in  such  wounds.  A  species 
of  particular  importance  is  the  Black  Blowfly  (Phormia  regina 
Meig.),  which  oviposits  in  soiled  wool  of  sheep.  The  larvae  feed 
in  the  soiled  wool  and  later,  after  the  skin  becomes  irritated  and 
sore,  enter  the  flesh.  Sanitary  measures  and  the  control  measures 
advocated  for  the  screw-worm  will  be  effective  for  this  fly. 

The  Horse  Bots  * 

Horse  bots  are  of  three  kinds,  one  of  which  is  of  rather  restricted 
range.  The  common  horse  bot  (Gastrophilus  intestinalis  DeGeer) 
is  most  abundant  over  the  entire  country.  The  Chin  fly  or  throat- 
bot  {G.  nasalis),  is  also  rather  common  and  widely  distributed. 
The  third  species,  the  nose-fly  (G.  hcBmorrhoidalis) ,  is  found  only 
in  the  North  Central  states  and  those  to  the  west  of  that  group. 

Bot  flies  vary  a  little  in  size  and  general  appearance,  but  all 
resemble  bees  to  some  extent.  The  common  bot-fly  is  seen  in  kte 
summer  la3dng  its  eggs  on  the  horses.  It  looks  like  a  bee  with  a 
long  slender  abdomen  which  is  doubled  forward  beneath  the  rest 
of  the  body  and  between  the  fore  legs.  The  throat-bot  is  smaller 
and  more  hairy  but  otherwise  similar. 

*  Family  Oestridw.      See  W.  E.  Dove,  Bulletin  597,  U.  S.  Dept.  of  Agr. 


662       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Eggs  of  the  common  bot  fly  are  small,  oval,  yellow  objects  com- 
monly called  nits,  and  attached  to  hairs  on  the  fore-quarters  of  the 
horse.  The  horse  hcks  them  off  and  they  hatch  in  the  mouth, 
making  their  way  into  the  stomach.  Here  they  live  some  months, 
passing  out  with  the  excrement  in  the  spring  or  early  summer  and 
pupating  in  the  soil.  Injury  is  due  to  malnutrition  and  to  the 
irritation  of  the  tissues  of  the  stomach . 

The  throat-bot  differs  in  its  habits  in  some  details  from  the 
common  bot-fly.     It  generally  lays  its  eggs  just  under  the  chin  or 


Fig.  581. — Bots  attached  to  the  wall  of  the  stomach  of  a  horse.     (After 
Osborn,  U.  S.  Dept.  of  Agr.) 

jaws.  The  larvae  of  this  species  sometimes  attach  themselves  in 
the  pharynx  where  they  may  seriously  interfere  with  taking  food 
or  even  with  the  breathing.  They  attach  also  in  the  stomach  but 
are  most  frequently  found  in  the  duodenum  where  they  may  be 
so  numerous  as  to  interfere  with  the  passage  of  the  excreta,  in 
which  case  serious  consequences  ensue. 

The  nose-fly  attaches  its  eggs  usually  on  hairs  on  the  lips  and 
it  causes  much  more  excitement  to  the  animal  in  the  process  than 
do  the  other  species.  Apparently  the  egg-laying  in  this  situation 
is  attended  by  some  pain  to  the  animal.  The  larvae  attach  in  the 
stomach  or  duodenum  and  later,  when  nearly  or  quite  grown 
reattach  themselves  in  the  rectum  or  anus,  causing  acute  discom- 
fort to  the  animal  and  interfering  with  the  passage  of  the  excreta. 


INSECTS  INJURIOUS  TO  DOMESTIC  ANIMALS,  Etc. 


663 


Full  grown  larvae  of  all  species  drop  to  the  ground  and  pupate 
in  the  soil. 

Work  horses  and  horses  kept  in  stables  and  given  daily  care  can 
be  protected  from  bot  flies  by  treating  the  eggs  every  few  days  with 
benzine,  kerosene  or  carbolic  preparations  or  by  clipping  the  hair. 
Horses  in  pastures  or  on  the  range,  especially  colts  which  are  most 
frequent  sufferers,  can  not  be  so  easily  protected.     Mechanical 


Fig.  582. — Horse  protected  from  attack  of  bot-flies.  After  Dove,  U.  S.  Dept. 
of  Agr. 

devices  have  been  suggested  to  protect  the  animals,  especially 
from  the  nose  fly.  A  muzzle  which  has  given  some  protection  is 
copied  from  W.  E.  Dove,  I.  c.     (See  Fig.  582). 

If  animals  be  furnished  shelter  which  is  somewhat  darkened 
for  the  daylight  hours  and  be  encouraged  to  graze  at  night,  con- 
siderable protection  will  result  since  the  bots  are  active  only 
during  the  daytime. 

Internal  treatments  to  rid  the  infested  animals  of  bots  have 
been  tried.  The  one  recommended  by  the  Department  of  Agri- 
culture is  quoted  below  from  Dove. 


664       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

"  The  day  preceding  the  treatment  a  small  amount  of  hay  and 
a  moderate  amount  of  oats  is  given  in  the  morning;  in  the  evening 
food  is  withheld  and  a  purgative  given — Barbadoes  aloes  1  ounce, 
or  raw  linseed  oil  1  pint.  The  day  of  the  treatment,  at  6  o'clock 
in  the  morning,  give  3  drams  of  carbon  disulphid  in  a  gelatin 
capsule;  at  7  o'clock  repeat  the  dose  in  the  same  manner;  and  at 
8  o'clock  give  the  third  and  last  dose,  making  in  all  9  drams  of 
carbon  disulphid  in  three  gelatin  capsules. 

"  The  above  treatment  is  for  the  adult  horse.  For  a  yearling 
colt  half  the  quantity  of  carbon  disulphid  used  for  a  mature  horse 
will  give  the  desired  results.  If  properly  administered  the 
gelatin  capsule  reaches  the  stomach  intact,  but  soon  dissolves  and 
the  carbon  disulphid  rapidly  evaporates,  suffocating  all  bot 
larvae  and  other  parasites  with  which  it  comes  in  contact,  but 
not  injuring  the  horse.     Worms  are  quite  often  expelled  as  well." 


The  Ox-warble  * 

The  Ox  Warble  is  most  prominent  in  the  spring  when  it  makes 
itself  apparent  in  the  swelhngs  or  warbles  on  the  backs  of  cattle. 

It  is  the  larva  of  a  fly  somewhat 
like  the  horse-bot  fly  but  more  like 
a  drone  bee. 

The  flies  lay  their  eggs  on  the 
legs  and  feet  and  the  lower  part  of 
the  body  of  the  animal.     Here  they 
hatch  and  fall  to  the   ground  at- 
taching   themselves   to   stems    of 
grasses  with  which  they  are  taken 
into  the  mouth  of  the  animal,  pass 
into  the    oesophagus    and  burrow 
their  way  into  the  thick  walls  of  the 
oesophagus    where    they    may   be 
found    in    animals  killed  in  early 
fall.    From  this  location  they  make 
their  way  between  the  muscles  until  they  finally  lodge  just  beneath 
the  skin  of  the  back  where  they  complete  their  development,  cause 
the  characteristic  swellings  and  finally  emerge  through  small  hole^ 
*  Hypoderma  lineata  Villers,  Family  Oestridae. 


Fig 


583.— The  Ox  Warble,  female. 
From  "Insect  Life." 


INSECTS  INJURIOUS  TO  DOMESTIC  ANIMALS,  Etc.      665 

which  they.have  made  some  time  before,  in  the  skin  of  the  back 
They  drop  to  the  ground  in  the  spring  and  pupate,  the  flies  emerg- 
ing in  early  summer. 

The  injury  is  from  the  irritation  which  they  cause  and  also 
from  the  damage  to  hides  caused  by  the  presence  of  the  exit  holes 
of  the  warbles. 

Control  of  the  ox  warble  is  difficult.  The  usual  practice  is  to 
destroy  them  by  removing  the  grubs  from  the  backs  of  cattle 


Fig.  584. — Young  stages  of  the  Ox  Warble.     From  "Insect  Life." 

when  the  lumps  appear.  This  is  done  by  squeezing  them  out 
through  the  exit  holes.  It  is  a  good  plan  to  treat  the  wound  with 
a  mild  antiseptic  solution  after  removing  the  maggot. 

Cattle  may  often  be  seen  standing  in  water  where  it  is  available 
in  pastures.  This  protects  the  submerged  parts  of  the  body  from 
the  oviposition  and  may  be  of  considerable  value.  If  running 
water  is  available  for  pastures  it  is  of  advantage.  Young  larvae, 
falling  into  running  water  will  be  carried  away  and  not  taken  into 
the  animal  with  the  water  which  is  drunk  as  sometimes  probably 
happens  in  stagnant  pools.  Stabling  during  the  day  time  and 
grazing  at  night  during  the  fly  season  is  always  good  practice 
where  it  can  be  done. 


666       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


A  different  species  {Hypoderma  hovis)  is  common  in  Europe  and 
has  been  found  in  Canada  and  several  localities  in  the  United  States. 

There  is,  after  years  of  study  and  observation  of  the  ox-warbles, 
still  some  difference  of  opinion  as  to  how  they  get  to  their  final 
location  under  the  skin  of  the  back.  Some  claim  that  they  bore 
through  the  skin  of  the  lower  parts  of  the  body  and  crawl  beneath 
the  skin  to  the  back.  Some  observations  to  confirm  this  have  been 
recorded.  The  other  conmion  belief  is  that  the  eggs  are  taken 
into  the  mouth,  where  they  hatch  and  work  through  the  walls  of 
the  oesophagus. 

The  Sheep  Grub  * 

The  third  important  example  from  the  bot-fly  family  is  the 
sheep  grub.  The  adult  of  this  species  is  smaller  than  that  of  the 
preceding  but,  like  it,  has  some  resemblance  to  a  honey-bee. 
Adults  are  present  throughout  the  summer  and  lay  their  maggots 

(the  eggs  being  hatched  in  the 
body  of  the  female)  in  the  nos- 
trils of  the  sheep.  The  larvae 
then  work  their  way  up  the 
nasal  passages  and  into  the 
frontal  sinuses  and  sometimes 
even  into  the  brain.  They 
cause  trouble  familiar  to  sheep 
men  under  the  name  of  the 
blind-staggers  or  gid.  Symp- 
toms are  giddiness,  or  in- 
FiG.  585.— Sheep  bot  flies  with  larviJe  and  abihty  to  control  movements 
pupa.     (After  Riley.)  naturally,  loss  of  appetite  and 

even  death.  The  larvae  remain  in  the  head  of  the  animal  for  as 
much  as  ten  months,  being  sneezed  out  at  maturity.  They  pupate 
in  the  ground  and  emerge  as  adults  in  some  four  to   six  weeks. 

Remedies  are  difficult  to  advise.  Prevention  of  oviposition  by 
providing  darkened  shelters  for  the  daytime  or  by  smearing  the 
noses  of  the  animals  with  tar  will  be  of  value.  Tar  may  be 
renewed  by  the  sheep  in  this  way:  Place  small  logs  here  and 
there  in  the  pasture.     Bore  in  these  several  holes  with  a  two-inch 

*  CEstris  ovis  L.     Family  (Estridoe. 


INSECTS  INJURIOUS  TO  DOMESTIC  ANIMALS,  Etc.        667 


augur  and  put  salt  in  the  holes.  Around  each  hole  smear  a  quantity 
of  tar.  Sheep  seeking  salt  will  got  the  tar  on  their  noses  and  be 
protected  in  a  measure  as  long  as  it  remains. 

It  is  difficult  to  rid  the  sheep  of  the  maggots  once  they  have 
become  established.  In  their  early  stages  they  may  be  reached 
by  injection  through  the  nostrils  but  later  this  is  not  practical. 
It  should  be  done  at  any  time  under  the  advice  of  a  veterinarian. 

Lice  of  Live  Stock  * 

There  are  two  general  groups  of  lice  which  may  affect  live- 
stock. These  are  the  biting  lice,  Mallophaga,  which  feed  on  hair, 
scales  from  the  epidermis  and  other  waste  on  the  animal,  but  are 
irritating  to  the  animal  and  cause  poor  general  condition,  and  the 
true  Uce  or  sucking  lice, 
Siphunculota  which  suck 
blood  from  the  host. 


Biting  Lice  t 

There  are  several  species 
of  biting  lice  to  be  found  on 
domestic  animals.  Aside 
from  the  ones  on  poultry 
the  most  conunon  are  the 
biting  lice  of  cattle  {Tricho- 
dedes  scalaris).  These  are 
small  whitish  forms  about 
one-sixteenth  of  an  inch  in 
length  and  of  the  general 
form  shown  in  the  illustra- 
tion. 

A  similar  species  occurs 
on  the  horse.  It  may  be 
a  trifle    larger  and   lighter 


Fia.  586. 


The  biting  louse   from  cattle. 
U.  S.  Dept.  of  Agr. 

in  color  but  otherwise  will  appear  just  as  the  cattle  louse.     Its 

specific  name  is  T.  parumpilosus.     Biting  lice  on  other  live  stock 

are  more  rare,  but  may  occur. 

*  See  Marion  Imes,  Farmers'  Bulletin  909,  U.  S.  Dept.  of  Agr. 
t  Mallophaga. 


668 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Sucking  Lice  * 

The  common  sucking  louse  of  cattle  is  the  short-nosed  ox- 
louse  (H (smatopinus  eurysternus).  It  is  bluish-gray  in  color 
and  considerably  larger  than  the  biting  louse,  being  about  one- 


FiG.  587. — The  short-nosed  ox-louse.     U.  S.  Dept.  of  Agr. 

eighth  inch  in  length.  The  head  of  this  species,  as  well  as  the 
other  species  of  sucking  lice,  is  rather  pointed  while  the  heads 
of  the  biting  species  are  more  rounded. 

The  long-nosed  ox-louse  (H.  vituli),  is 
longer  and  more  slender  than  the  short- 
nosed  louse.  It  is  generally  less  in 
jurious. 

The  long-nosed  hog-louse  (H.  suis), 
is  the  largest  member  of  this  group 
which  is  at  all  common.  It  is  nearly  a 
quarter  of  an  inch  long  and  is  broad 
across  the  abdomen.  It  is  found  on  hogs 
frequently  and  is  said  to  be  the  worst 
enemy  of  swine  next  to  the  cholera.  Lice  Fig.  588. — Long  nosed  ox- 
are  easier  to  eradicate  on  swine  than  louse.  U.  S.  Dept.  of  Agr. 
on  the  larger  animals,  so  only  neglect  need  cause  loss  from  them . 
A  biting  louse  (H.  pedalis),  is  found  on  the  feet  and  legs  of 
sheep,  below  the  long  wool  but  it  is  rare  and  does  little  injury. 
Dogs  occasionally  become  infested  with  nce,both  sucking  and  biting. 

*  Siphunculata 


INSECTS  INJURIOUS  TQ  DOMESTIC  ANIMALS,  Etc.       669 


Control  of  Lice 

Lice  may  be  killed  by  the  use  of  dips  as  recommended  for 
other  parasites.  Spraying  the  animals  with  nicotine  or  kerosene 
emulsion  will  be  effective  provided  all  parts  are  wet  with  the 
spray  clear  to  the  skin.  Some  danger  of  colds  to  the  animals 
must  be  considered  when  they  are  being  dipped  or  sprayed. 

Sulphur  or  sulphur  and  lard,  thoroughly  applied,  will  kill  lice. 

Experiments  at  the  West  Virginia  Station  have  shown  that 
lice  on  an  animal  can  be  killed  by  the  use  of  blue-ointment. 
This  is  applied  over  a  small  area,  two  inches  wide  and  six  inches 
long,  on  the  side  of  the  neck  or  elsewhere,  so  it  can  not  be  reached 
by  the  animal.  A  small  amount  of  the  ointment  is  thoroughly 
rubbed  into  the  skin.  In  a  short  time  the  lice  disappear.  Just 
what  the  action  is,  is  not  known.  Precautions  must  be  taken  to 
keep  the  animals  from  licking  the  parts  treated.  This  is  easy 
in  the  case  of  hogs  and  horses,  but  more  difficult  with  cattle  which 
often  lick  each  other.  It  will  always  be  well  to  cover  the  treated 
parts  with  burlap,  fastening  it  securely  so  that  it  can  not  be 
rubbed  off  and  replacing  it  immediately  if  it  becomes  loosened. 

The  Sheep  Tick  * 

The  Sheep  Tick  is  not  a  tick  at  all  except  in  general  appear- 
ance, but  a  wingless  fly.  The  insect 
spends  the  entire  life  on  the  sheep,  suck- 
ing blood  from  the  host  for  nourish- 
ment. Development  in  this  group  is 
unusual,  the  young  being  retained  in 
the  bodies  of  the  females  as  larvse  until 
ready  to  pupate  and  being  deposited  not 
as  eggs  but  as  pupae,  which  are  glued 
to  the  wool  of  the  sheep.  The  effect 
of  these  parasites  on  the  host  is  to  lessen 
their  vitality.  This  is  generally  in- 
dicated by  the  condition  of  the  wool, 
which  is  rough  and  scraggly. 

Sheep  ticks  can   be   controlled   by 

dipping  the  animals  in  Blackleaf  40  diluted  1  to  1000.     This  is 

best  done  at  shearing  time,  as  when  the  wool  is  long  it  is  almost 

*  Melophagus    ovinus    L.     Family    Hippoboscidcp.     Order     Diptera.     See 
Marion  Imes,  Farmers'  Bulletin  798,  U.  S.  Dept.  of  Agr. 


Fig.  589.— The  Sheep  Tick. 
K3\  Agr.  Exp.  Sta. 


670         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

impossible  to  get  the  dip  to  penetrate  to  all  the  ticks.  Migra- 
tion from  animal  to  animal  is  slow  and  flocks  once  freed  from  the 
ticks  may  be  kept  free  by  keeping  out  infested  animals.  Most  of 
of  the  ticks  are  removed  with  shearing  and  sometimes,  if  the  lambs 
do  not  become  infested,  shearing  will  eliminate  the  necessity  for 
special  treatment. 

Dipping  for  this  and  other  pests  will  be  discussed  more  in 
detail  at  the  end  of  the  chapter. 

Scab  Mites* 

Scab  mites  attack  cattle  and  sheep,  causing  a  diseased  con- 
dition called  scabies.  Similar  mites  attack  horses,  hogs  and  man, 
causing  the  irritation  called  itch  or,  in  animals,  mange.  The 
more  important  of  these  are  the  species  affecting  cattle  and  sheep. 

Cattle  Scab  or  Scabies  * 

The  organism  causing  cattle  scab  is  a  minute  mite,  and  like 
other  mites  is  not  an  insect  but  a  member  of  the  order  A  carina. 


Fig.  590.— Sheep  scab-mite.     (After  Good,  Ky.  Agr.  Exp.  Sta.) 

The  mite  is  a  minute  oval  object  but  is  visible  to  the  unaided  eye. 
Eight  short,  tapering  legs  project  from  the  margin  of  the  body 

*  Psoroptes  communis  bovis.     See  Marion  Imes,  Farmers'  Bulletin  1017, 
U.  S.  Dept.  of  Agr. 


INSECTS  INJURIOUS  TO  DOMESTIC  ANIMALS,  Etc.      671 

in  different  directions  like  the  spokes  of  a  wheel.  The  entire 
life  is  spent  on  the  host  and  the  life  cycle  requires  about  two 
weeks.     Multiplication  is  rapid. 

Symptoms  include  a  roughened  condition  of  the  coat  on  the 
infected  areas,  this  gradually  spreading  all  over  the  body  and 
being  followed  by  shedding  of  the  hair  and  a  scabby  appearance 
of  the  skin,  caused  by  the  burrowing  of  the  mites  and  the  conse- 
quent irritated  condition. 

Control  of  scabies  is  secured  through  the  use  of  dips.  Of 
these  the  lime-sulphur  compounds  are  recommended,  since  they 
kill  all  the  parasites  which  may  be  on  the  animal.  Dipping  will 
be  discussed  separately  since  it  is  the  treatment  recommended 
for  several  of  the  parasites  of  stock. 

Sheep  Scab  * 

The  organism  causing  the  sheep  scab  is  merely  a  variety  of 
the    one  causing  the  scab  of    cattle,  Psoroptes  communis   ovis, 


Fig.  591. — Sheep  infected  with  scabies.     Early  and  late  stages.     Ky.  Agr 

Exp.  Sta. 

being  the  name  for  the  sheep  scab  organism  and  P.  communis 
bovis,  being  responsible  for  the  cattle  scab.  A  third  variety 
P.  communis  equi,  causes  the  scab  of  horses. 

The  life^history  of  the  sheep  scab  mite  is  the  same  as  for 
*  See  Marion  Imes,  Farmers'  Bulletin  713,  U.  S.  Dept.  of  Agr. 


672      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

the  cattle  scab  and  the  symptoms  are  similar.  Shedding  of  the 
wool  in  patches  is  an  advanced  symptom  in  sheep  while  a  ragged 
condition  of  the  wool  shows  earlier. 

Control  of  sheep  scab,  as  of  cattle  scab,  is  accomplished  by 
dipping,  the  same  dips  being  available  for  both. 

Mange  and  Scabies  of  Horses  * 

Scabies  of  horses  is  a  disease  similar  to  the  scabies  in  cattle. 
Mange  is  caused  by  a  mite  of  a  different  genus,  {Sarcoptes  scabei) . 
The  species  involved  has  several  varieties,  named  to  indicate  the 
host.  Thus  the  one  on  horses  is  equi,  on  dogs  it  is  called  canis,  on 
hog  suis,  while  the  same  mite  is  hominis  on  man.  The  mites  may 
be  transferred  from  one  host  to  another  but  generally  do  not  live 
long  except  on  the  original  host.  The  disease  caused  by  the  mange 
or  itch  mites  does  not  differ  materially  from  the  ordinary  scabies. 
Earliest  indications  of  infection  are  a  tendency  to  rub  affected 
parts,  the  hair  being  entirely  rubbed  off  in  spots. 

Treatment  of  mange  or  scabies  in  horses,  consists  of  rubbing  some 
solution  such  as  is  used  in  dips  into  the  skin  of  the  affected  parts, 
being  sure  that  the  entire  infected  area  is  treated  and  repeating  the 
process  three  or  four  times  at  intervals  of  about  four  days.  Lime- 
sulphur  solution,  as  recommended  for  dipping,  is  as  convenient 
and  satisfactory  as  anything.  Nicotine  preparations  will  also 
be  found  to  be  effective. 

Swine  Mange 

Swine  mange  manifests  itself  usually  on  the  upper  parts  of  the 
body  from  head  to  tail.  A  general  roughened  and  unhealthy 
appearance  of  the  skin  will  suggest  the  existence  of  the  disease. 
This  may  be  confirmed  by  the  finding  of  the  mites.  This  is  done 
by  scraping  off  the  skin  until  some  of  the  deeper  layers  are  reached 
and  examining  with  a  microscope. 

Treatment  consists  of  dipping  or  local  application  of  some  of 
the  dips  sold  for  the  purpose  or  of  home  made  lime-sulphur  solution. 
If  the  animals  are  dipped  the  dip  should  be  kept  at  about  body 
temperature. 

Ticks  Attacking  Cattle  * 

Several  species  of  ticks  attack  cattle  and  others  are  occasional 
parasites  of  other  animals  and  may  be  found  on  man.     Perhaps 
*  Order  Acarina. 


INSECTS  INJURIOUS  TO  DOMESTIC  ANIMALS,  Etc.        673 

the  most  serious  of  the  ones  attiusking  man  is  the  tick  which  has 
received  the  name  of  the  Rocky  Mountain  Fever  Tick  {Derma- 
centor  venustus,  Banks),  because  it  has  been  shown  to  be  an  agent 
in  the  transmission  of  the  fever  of  that  name,  which  is  a  highly 
fatal  disease  occurring  in  many  of  the  Rocky  Mountain  States  but 
most  prevalent  and  virulent  in  the  Bitter  Root  Valley  of  Montana. 
This  tick  spends  a  part  of  its  life  on  the  smaller  wild  mammals  and  a 
part  on  the  large  mammals,  wild  and  domestic.     Upon  occasion  it 


Fig.  592. — The  Rocky  Mountain  spotted  fever  tick.     (After  R.  A.  Cooley, 
Montana  Agr.  Exp.  Sta.) 

bites  man,  and  in  so  doing  may  infect  him  with  the  fever  if  it  has 
previously  received  the  virus  from  another  infected  person  or 
animal. 

The  Cattle  Tick  * 

The  most  important  of  the  cattle  ticks,  and  one  of  the  most 
important  of  the  arthropods  affecting  the  cattle  industry,  is  the 
Texas  Fever  Tick  or  North  American  Fever  Tick,  a  common 
pest  of  cattle  in  the  South  and  the  sole  means  for  the  trans- 
mission of  the  disease  known  as  Texas  Fever.  This  disease  and 
so  the  tick,  has  been  the  greatest  obstacle  to  the  establishment  of 
the  livestock  industry  in  regions  of  the  South  which  are  otherwise 
well  adapted  to  cattle  raising. 

The  fully  grown  adult  ticks  may  be  as  much  as  a  half  inch  long 
and 'are  thick  bodied  and  oval  in  shape.  The  head  is  much  smaller 
than  that  of  other  ticks  found  on  cattle  and  is  reddish  brown  in 
color.     Body  color  is  yellowish  or  a  dull  brown  with  mottling  of 

*  Margaropus  annulatus.  See  Farmers'  Bulletin  1057  and  numerous  other 
U.  S.  Dept.  of  Agr.  publications. 


674 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


yellow  or  brown  of  different  shades.  The  adult  female  becomes 
engorged  with  blood  and  eggs  and  drops  from  the  animal  to  the 
ground  where  she  lays  from  1500  to  3000  eggs.  From  these  eggs 
the  young  or  seed  ticks  hatch  in  from  two  to  six  weeks,  depending 
on  the  temperature.     The  young  seed  ticks  crawl  onto  grass  or 


4. 

^i»' 

^m 

i 

'  i 

'■ 

1 

O. 

^' 

5. 

ij 

^" 

'\f 

■-> 

Q5^ 

'\ 

Fig/SOS. — The  cattle  tick  (U.  S.  Dept.  of  Agr.):  3,  mature  female  with  eggs; 
4,  ticks  attached  to  the  hide;  5,  blood  cells  containing  Babesia  organisms; 
10,  various  stages  of  ticks.  Natural  size  except  5,  which  is  enlarged 
1,000  times. 

weeds  and  transfer  themselves  to  cattle  at  the  first  opportunity. 
If  they  fail  to  do  this  they  die,  but  not  necessarily  for  three  or  four 
months.  On  cattle  they  attach  themselves  to  the  tender  and 
protected  parts  and  suck  blood,  maturing  in  warm  weather  in  some 
SIX  weeks.     If  the  parent  of  these  ticks  was  from  an  infected  animal, 


INSECTS  INJURIOUS  TO  DOMESTIC  ANIMALS..  Etc.       675 


they  may  infect  the  new  host  with  the  Texas  fever  at  this  stage, 
even  though  they  are  so  small  as  to  be  scarcely  visible. 

Texas  fever  is  caused  by  a  minute  protozoan  animal  of  the  same 
general  group  as  the  parasite  causing  malaria  (Babesia  higemina.) 


FIELD  NO. 2 

CORN. 

COhTt/IS 

FIELD  N0.3. 

COTTON   FOLLOWED 

BY  ertiMsON cLOV[:fi,v£rcn. 
Buft  ciovefi  OP  pye 

FIELD  NO.^ 

0/ITS., 

COWPE/IS, 
BEHMUO/I, 

BUR  cLoven 

MOVE  THE  HERD  FMM 

THI5  FIELD  TO  FIELD 

N0.3. 

FFBR.IS.MOl'ETHEHCRB 
T{>  FIELD  NO.  4-. 

BECOMES  THE  NEh/ 
P/ISTUHL. 

Illlllllllll 
HOUSE 

FIELD  NO  1 
P/!6TUKE. 
OCT  IS.  MOVE  HE  FID  TO  FIELD  NO.Z. 
PL/INT    IN    0/>T^    AND    FOLLOW  WITH    COInlPE/li 

Fig.  594. — Plan  for  freeing  cattle  and  pastures  from  ticks  by  rotation,  requir- 
ing eight  months,  U.  S.  Dept.  of  Agr. 

It  passes  from  the  body  of  the  infected  female,  no  one  knows  just 
how,  into  the  eggs  so  that  all  her  progeny  are  infective.  Appar- 
ently healthy  cattle  from  permanently  infected  districts  are  usually 
carriers  of  the  disease  but  have  developed  immunity  to  the  effects. 
They  are  as  dangerous  as  sources  of  infection  for  the  ticks  as  are 
the  cattle  sick  with  the  disease. 

It  has  been  definitely  shown  that  the  disease  can  not  be  trans- 
mitted in  nature  in  any  way  except  by  the  bites  of  the  infected 
ticks.  That  being  the  case,  the  obvious  way  to  eliminate  the 
disease  is  to  destroy  the  ticks.     The  U.  S.  Department  of  Agri- 


676  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


culture  and  the  authorities  in  several  of  the  southern  states  have 
worked  out  a  plan  whereby  it  is  possible  to  eradicate  the  tick  from 
the  entire  Texas  fever  area.  This  makes  use  of  the  habits  of  the 
ticks  and  the  fact  that  they  have  no  alternate  host.  The  general 
scheme  is  a  system  of  rotation  of  pastures.  Cattle  are  removed 
from  infested  pastures,  dipped  to  free  them  from  ticks  remaining 
on  them  or  not,  depending  upon  the  number  of  pastures  available. 


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Fig.   595. — Plan  for  freeing  cattle  and  pastures  from   ticks  by  rotation, 
requiring  four  months,  with  new  pasture,  U.  S.  Dept.  of  Agr. 

The  infested  pasture  is  then  plowed  up  or  allowed  to  remain  idle 
for  some  four  months  by  the  end  of  which  time  all  ticks  in  it  will 
have  died.  If  there  are  tick  free  pastures  available,  the  cattle 
from  the  first  pasture  may  be  dipped  to  kill  the  ticks  upon  them 
and  then  placed  in  the  tick-free  pasture,  care  being  taken  not  to 
introduce,  at    any  time,  tick-carrying   cattle  into   this  pasture 


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678  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

After  four  months  they  may  be  removed  back  to  the  original 
pasture.  If,  however,  no  tick-free  pasture  is  available,  a  different 
scheme  is  used.  The  cattle  are  moved  after  as  many  of  the  adult 
ticks  have  dropped  to  the  ground  as  are  likely  to  drop  off  soon. 
They  are  then  taken  to  another  pasture,  still  infested  at  this  time. 
Here  they  remain  not  more  than  twenty  days  when  they  are  re- 
moved to  a<third  field  where  they  remain  another  twenty  days,  and 
then  to  a  fourth  field  where  they  remain  until  they  are  free  of  ticks, 
but  from  which  they  are  removed  before  any  seed  ticks  appear  in 
the  fifth  field.  This  field  is  by  this  time  tick-free  and  the  cattle 
may  remain  there  until  the  original  field  has  had  time  to  become 
free,  which  is  usually  shortly  after  this  time.  The  time  required 
depends  upon  the  season  of  the  year  in  which  it  is  started.  The 
accompanying  diagram  shows  the  general  scheme  of  rotation  in 
practice. 

The  whole  tick-infested  area  was  placed  under  quarantine  in 
1906  by  the  Federal  authorities  and  movements  of  cattle  from  the 
quarantined  area  were  permitted  only  under  supervision.  Since 
that  time  large  parts  of  the  quarantined  area  have  been  freed  from 
ticks  and  the  quarantine  removed.  The  map  shows  the  wonderful 
progress  of  this  work.  It  is  surely  only  a  matter  of  a  few  years 
until  the  Texas  fever  tick,  and  with  it  the  fever,  wiU  have  disap- 
peared from  the  United  States. 

Dipping  Live  Stock  for  Parasites 

Many  of  the  external  parasites  are  best  treated  by  dipping 
them  or  immersing  them  in  some  solution  of  an  insecticidal  nature. 
Lice,  sheep  ticks,  ticks  on  cattle  and  the  mites  causing  mange  and 
scabies  all  may  be  killed  in  this  manner. 

Numerous  dipping  solutions  or  dips  have  been  tried  out  and 
recommended.  Only  those  which  are  applicable  to  the  majority 
of  the  pests  in  question  will  be  mentioned  here. 

Nicotine  is  a  standard  dipping  material.  It  should  be  used  at 
a  strength  containing  approximately  five  one-hundredths  of  one 
per  cent  of  nicotine.  This  strength  corresponds  to  Black-leaf 
40  diluted  one  to  800.  Other  dips  should  be  used  in  the  same 
proportionate  strength,  dilution,  for  commercial  products  being 
usually  indicated  on  the  package. 


INSECTS  INJURIOUS  TO  DOMESTIC  ANIMALS,  Etc.        679 

Lime-sulphur  solutions  have  long  been  used  for  dipping  cattle, 
having  been  manufactured  for  that  purpose  before  they  were  used 
for  spraying.  They  do  not  differ  in  composition  from  the  same 
materials  used  as  sprays.  Strengths  of  commercial  materials 
will  be  indicated  on  the  package.  Home-made  materials  should 
contain  8  pounds  unslaked  lime  and  24  pounds  sulphur  to  the 
hundred  gallons.  The  process  of  cooking  is  the  same  as  for  the 
spray  of  the  same  materials. 

Sulphur  and  nicotine  in  combination  have  been  used  for 
dipping.  In  this  dip  flowers  of  sulphur  is  mixed  with  the  nicotine, 
the  amount  necessar}'^  to  make  a  1  to  800  solution  of  nicotine  con- 
taining two  per  cent  of  sulphur  being  used.  These  are  then 
added  to  the  water. 

Widely  used  dips  for  various  purposes  are  the  arsenical  dips. 
Arsenical  dips  may  be  made  by  using  caustic  soda,  4  pounds, 
white  arsenic  10  pounds  and  sal-soda  crystals  10  pounds.  Dis- 
solve the  caustic  soda  in  about  a  gallon  of  hot  water  and  add  the 
arsenic  as  fast  as  it  can  be  dissolved  in  the  hot  water  without 
boiling,  then  dilute  to  about  four  gallons  and  add  the  sal-soda, 
then  dilute  the  whole  to  exactly  five  gallons.  This  forms  one 
of  the  two  necessary  stock  solutions.  The  other  is  made  as 
follows:  Dissolve  ^-pound  caustic  soda  in  a  quart  of  water, 
then  add  a  gallon  of  pine  tar,  stirring  until  a  smooth  even  mixture 
is  secured.  Both  the  above  sto^k  solutions  should  be  kept  in 
closed  containers.  The  diluted  dipping  solution  for  use  should 
contain  four-fifths  of  a  gallon  of  the  arsenic  stock  and  one-third 
gallon  of  the  tar  stock. 

Other  dips  are  made  from  coal-tar  preparations,  but  are  usually 
sold  as  proprietary  dips,  and  should  be  used  as  directed. 

Dipping  vats  are  of  many  styles.  For  large  stock  ranches 
they  may  be  made  permanent  and  arranged  so  as  to  handle 
large  numbers  of  animals.  Smaller  farms  may  well  have  per- 
manent vats  which  need  not  be  so  elaborate.  For  small  animals, 
sheep  for  instance,  vats  are  not  necessary  but  are  desirable  for 
convenience  in  handling  the  animals.  Sheep  may  be  dipped  in 
large  barrels.  A  canvas  bag  for  dipping  sheep  has  been  used  with 
satisfaction  in  small  operations. 

Anyone  contemplating  the  use  of  dips  or  the  construction  of 
dipping  vats  and  apparatus  should  consult  the  Bureau  of  Animal 


680 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Industry,  U.  S.  Dept.  of  Agriculture,  or  the  State  Experiment 
Station,  which  will  give  free  advice  and  often  will  be  able  to 
send  experts  to  assist  in  the  pi^eparation  for  such  work.  Farmers' 
Bulletins  Nos.  1057,  713,  909,  798,  and  603  deal  with  pests  for 
which  dips  are  used  and  with  the  preparation  of  dips  and  dipping 
vats,  and  should  be  consulted  before  beginning  such  work.  They 
like  all  Farmers'  Bulletins,  are  free  upon  application  to  the  U.  S. 
Department  of  Agriculture,  Washington,  D.  C. 

Poultry  Lice  * 

Only  the  biting  lice  attack  poultry  or  birds  of  any  kind,  the 
sucking  lice  being  found  exclusively  on  mammals.     Three  species 
are   common  on  chickens  and  others  are 
occasionally  found.     Different  species  at- 
tack ducks,  turkeys  and  other  fowls. 

The  Head  Louse  of  Chickens  f 

This    louse  is  most  frequently  found 

on  the  head  but  may  occur  on  the  neck 

and   other  parts.      It  is  dark  grayish  in 

color  and  may  be  as  long  as  one-tenth  inch. 

Eggs  are  deposited  on  the  down  or  feathers 

about  the  head  and  the  lice  feed  on  the  skin 

and  feathers  close  to  the  skin.     The  life 

cycle  requires  about  three  weeks.      Young 

resemble  the  adults  except  in  size  and  in 

their  lighter  color.     It  is  this  species  that 

causes  most  trouble  with  young  chicks  to 

which  it  passes  readily  from  the  mother  hen. 

As  the  chickens  get  older  these  lice  become 

less   numerous   and    troublesome.      Since 

Fig.   597. —  Head  louse:  poultrymen  insist  that  profits  from  poultry 
male,  top  view.   Greatly        ...  ,  ,         ,  .         . 

enlarged.     After  Bish-  raismg  depend  very  largely  upon  the  vigor 

opp,U.  S.Dept.  of  Agr.  of  young  chicks  it  will  be  seen  that  the 

control  of  these  lice  is  important.     This  may  be  accomplished  as 

described  later  for  all  poultry  lice. 

*  Order  Mallophaga.     See  F.   C.   Bishopp  and  H.   P.   Wood,   Farmers' 
Bulletin  801,  U.  S.  Dept.  of  Agr. 
t  Lipeurus  heretographus  Nitzsch. 


INSECTS  INJURIOUS  TO  DOMESTIC  ANIMALS,  Etc.        681 


The  Body  Louse  of  Chickens  * 

Possibly  the  most  common  of  the  chicken  lice  is  this  species 
It  is  found  on  the  skin  of  the  fowl 
rather  than  on  the  feathers,  but 
may  occur  on  the  neck  and  head 
as  well  as  on  the  body.  It  is  found 
most  frequently  just  below  the 
vent  but  may  occur  in  numbers 
on  other  regions  of  the  body  and 
on  the  thighs.  Eggs  are  laid  in 
clusters  near  the  base  of  the 
feathers,  being  most  numerous  in 
the  regions  where  the  lice  are  found 
in  greatest  numbers.  The  com- 
plete life  cycle  requires  about  a 
month,  but  there  is  little  difference 
between  the  young  and  the  adults 
except  in  size.  The  color  is  yel- 
lowish and  the  size  of  the  grown 
forms  is  about  one-twelfth  of  an 
inch  in  length.  This  species  does 
the    most 


Fig.  598  —  Body  louse:  female  un- 
derside. Greatly  enlarged.  After 
Bishopp,  U.  S.  Dept.  of  Agr. 


damage     to     adult    chickens. 

The  Shaft  Louse  f 

This  species  is  smaller  than  the  body 
louse  and  is  sometimes  called  the  small 
body  louse  although  it  is  found  on  the 
feathers  rather  than  on  the  body.  It  is 
found  on  the  shaft  of  the  feathers  where  it 
feeds  on  the  barbs,  for  this  reason  being 
less  injurious  than  the  other  species  men- 
tioned, both  of  which  feed  on  the  skin  to 
a  great  extent. 

Control  of  Chicken  Lice  * 

Control  of  these  forms,  as  is  the  case  with 
so  many  other  pests,  is  best  accomplished  by 
prevention.      If    the  premises  and  fowls 
Menopon  biseriatum  Piaget.  f  Menopon  pallidum  Nitzsch. 


Fig.  599.  —  The  Shaft 
Louse.  U.  S.  Dept. 
of  Agr. 


682       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

can  once  be  entirely  freed  from  lice,  they  may  be  kept  so  by  keep- 
ing away  all  stray  fowls  and  by  thorough  treatment  of  new  stock 
may  be  brought  in  from  the  outside.  To  rid  a  flock  of  Kce,  the 
best  time  to  do  the  work  is  late  summer  or  fall,  preferably  before 
the  moulting  period,  and  when  there  are  as  few  fowls  in  the  flock 
as  will  likely  be  kept  at  any  time. 

Experiments  by  Bishopp  and  Wood  have  shown  that  the  best 
material  for  treatment  is  sodium  fluoride,  which  is  obtained  in  the 
form  of  a  dry  powder.  One  application  of  this  material,  properly 
used,  is  said  to  free  the  premises  entirely  from  lice. 

The  material  is  applied  either  as  a  dust  or  in  water  as  a  dip, 
the  action  as  a  dust  being  slower  than  when  applied  as  a  dip. 

Applied  as  a  dust  it  should  be  placed  in  small  quantities,  about 
what  can  be  picked  up  between  the  thumb  and  the  forefinger,  to  at 
least  a  dozen  different  places  on  the  body  of  the  fowl,  these  places 
to  be  distributed  as  evenly  as  possible.  Or  the  material  may  be 
sifted  into  the  feathers  while  they  are  ruffled  and  spread  out,  but 
this  method  is  not  as  convenient  as  the  so-called  pinch  method. 

Sodium  fluoride  for  dipping  should  be  used  at  the  rate  of  three- 
fourths  ounce  to  the  gallon  of  lukewarm  water  and  dipping  should 
be  done  toward  noon  on  a  warm  sunny  day.  The  water  should 
be  placed  in  a  tub  and  the  fowls  dipped  directly  into  the  water, 
the  feathers  being  ruffled  while  the  bird  is  submerged  to  allow 
the  water  to  penetrate.  The  head  is  immersed  once  or  twice 
after  the  rest  of  the  body  has  been  dipped.  This  method  is 
quicker  than  the  pinch  method  but  should  not  be  used  in  cold 
weather  unless  one  has  heated  poultry  houses  to  work  in. 

In  West  Virginia  it  has  been  found  that  a  pinch  of  blue- 
ointment  rubbed  into  the  skin  just  below  the  vent  and  another 
on  the  head  and  under  the  wings,  will  rid  the  fowls  of  lice  but  that 
this  method  must  not  be  used  for  young  chicks  or  for  hens  brooding 
young  chicks. 

Other  remedies  for  lice  have  been  tried,  but  in  view  of  the 
excellent  results  from  the  sodium  fluoride  treatment  it  would 
seem  inadvisable  to  recommend  any  other  treatment. 


INSECTS  INJURIOUS  TO  DOMESTIC  ANIMALS,  Etc.      683 


Mites  on  Poultry  * 

The  Common  Chicken  Mite  (Dermanyssus  galUnae  DeGeer,) 
is  the  most  important  of  the  chicken  mites.  It  is  of  universal 
occurrence  in  this  country  where  there  are  chickens.  The  mite 
itself  is  a  minute  whitish  gray  object,  just  large  enough  to  be 
seen  in  good  light  with  the  unaided  eye.  The  mites  feed  on 
blood  from  the  chickens,  and  when  numerous  result  in  a  condition 
of  depleted  vitality  indicated  by  an  unthrifty  appearance.  The 
mites  feed  on  the  poultry  at  night  hiding  in  crevices  in  the  houses, 
about  the  roosts  and  on  the  floors  during  the  day.     The  life  cycle 


Fig.  600.— The  Common  Chicken  Mite,  U.  S.  Dept.  of  Agr. 

in  warm  weather  requires  only  a  week  so  the  increase  in  numbers 
may  be  extremely  rapid. 

Control  is  based  on  this  habit  of  leaving  the  fowls  in  the  day 
and  remaining  in  the  houses.  Application  of  many  different  kinds 
of  insecticides  will  kill  the  mites  if  thoroughly  done.  In  old  badly 
infested  houses  all  the  roosts  and  nests  should  be  removed,  all  the 
litter  burned  or  buried  deeply  and  the  nest  boxes  and  roosts 
themselves  burned  if  they  can  easily  be  replaced  as  is  often  the 
case.  The  house  should  then  be  sprayed  with  a  good  spray  from 
a  pump  which  will  give  plenty  of  pressure.  A  good  barrel  outfit 
will  be  satisfactory.  Good  results  can  be  secured  with  more  work, 
in  small  houses  by  the  use  of  some  small  atomizer  but  the  larger 
outfit  is  to  be  preferred.     The  spray  should  be  directed  at  different 


684 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


angles  toward  all  parts  of  the  house.  The  floor  should  be  soaked 
and  even  the  roof  or  ceiling  should  be  sprayed.  Spraying  the 
outside  will  help  to  give  complete  control  as  such  spray  will 
penetrate  cracks  which  have  not  been  reached  from  the  inside. 

Roosts  and  nests  should  be  made  as  simple  as  possible  and  as 
easily  removable,  for  the  sake  of  subsequent  treatments,  as  can 
be  arranged. 

Satisfactory  sprays  are  crude  petroleum,  thinned  with  one- 
fourth  its  volume  of  kerosene,  which  will  destroy  all  the  mites 
at  one  application ;  kerosene  or  kerosene  emulsion,  which  requires 
several  treatments;  lime-sulphur,  which  also  should  be  applied 
three  for  four  times  at  intervals  of  a  week;  whitewash,  to  which 
has  been  added  five  per  cent  of  crude  carbolic  acid  or  cresol. 
Nicotine  preparations  have  given  good  results  but  require  two  or 
three  applications  and  must  be  used  stronger  than  in  spraying 
plants. 

The  periodical  use  of  a  strong  whitewash  with  carbolic  acid 
added  is  a  good  sanitary  measure,  entirely  aside  from  its  effect 


Fig.  601. — Depluming  scabies  (C  laevis  var.  gallinae);  (a)  adult  male  (x  114); 
(6)  adult  female  (x  108).     (From  Mote,  after  Sim,  O.  Agr.  Exp.  Sta  ) 

on  the  mites  and  is  to  be  recommended.  If  this  is  done,  say  once 
every  two  or  three  months,  the  mites  will  probably  never  become 
numerous. 

Other  poultry  mites  include  the  Depluming  Mite  (Cnemido- 
coptes  gallinae  Railliet),  which  burrows  into  the  skin  of  the  fowl 


INSECTS  INJURIOUS  TO  DOMESTIC  ANIMALS,  Etc. 


685 


near  the  base  of  the  feathers.  The  intense  itching  caused  by  the 
mites  induces  the  fowls  to  pick  out  feathers  in  their  efforts  to 
allay  the  irritation. 

The  treatment  recommended  by  Bishopp  is  the  repeated  use 
of  sulphur  ointment,  well  rubbed  into  the  skin.     H.  P.  Wood 


U^' 


Fig.  602. — Scaly  leg  (C  mutans) :  (a)  leg  of  chicken  infested  by  mites  (reduced) : 
(b)  mite  in  burrow  in  skin  (x  60);  (c)  adult  female  (x  82);  (d)  adult  male 
(x  130).     (From  Mote,  after  Sim,  O  Agr  Exp.  Sta.) 

reports  *  complete  success  in  t/he  control  of  this  mite  as  well  as 
lice  by  dipping  the  fowls  in  a  solution  of  chemically  pure  sodium 
fluoride,  two-thirds  ounce,  sulphur  2  ounces,  laundry  soap  one- 
third  ounce  in  about  one  gallon  of  water.  Only  one  applica- 
tion was  found  necessary. 

The  Scaly-leg  Mite,  the  cause  of  the  chicken  disease  called 

*Journal  of  Econ:  Entomology,  Vol.  12,  No.  5. 


686      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

scaly-leg,  burrows  into  the  skin  and  beneath  the  scales  of  the 
feet  and  occasionally  gets  on  the  comb  and  the  neck.  The  legs 
become  encrusted  with  the  scaly  tissue  resulting  from  the  work 
of  the  mite  and  the  feet  sometimes  get  to  be  so  tender  that  the 
fowl  can  scarcely  walk. 

The  treatment  recommended  is  to  soak  the  leg*  in  warm  water 
so  as  to  soften  the  scales  and  then  to  dip  the  legs  into  crude 
petroleum.     The  same  material  applied  to  the  roosts  may  pre- 
vent the  spread  which  is  from  fowl  to  fowl  on  the  roosts. 

Chiggers,  the  same  as  those  found  attacking  man,  are  some- 
times troublesome  to  chickens  which  are  allowed  to  roam  in 
pasture  fields  grown  up  in  brush  as  is  common  on  farms.  Dusting 
with  sulphur  dust  and  keeping  chickens,  especially  the  young  ones, 
out  of  infested  pastures,  will  aid  in  the  control  of  the  chiggers. 

Other  Poultry  Pests 
Beside  the  mites  and  lice  named,  there  are  other  species  which 


Fia.    603. — The    sticktight    flea:  adult    female.     Much    enlarged.     (After 
Bishopp,  U.  S.  Dept.  of  Agr.) 

attack  chickens  and  each  other  kind  of  domestic  fowl  has  its  own 
species  of  these  insects.  These  differ  little  from  those  found  on 
chickens  and  will  respond  to  the  same  treatment. 


INSECTS  INJURIOUS  TO  DOMESTIC  ANIMALS,  Etc.      687 

Chickens  suffer  in  some  regions  from  the  attacks  of  a  flea,  the 
Chicken  Sticktight  Flea  (Echidnophaga  gallinacea  West  wood). 
This  flea  is  occasionally  found  on  dogs  and  cats,  and  on  other 
animals,  but  is  known  for  the  most  part  as  a  pest  of  chickens,  It 
occurs  in  the  southern  and  southwestern  states  more  abundantly 
than  elsewhere.  This  flea  is  dark  in  color,  almost  black,  and 
differs  from  other  fleas  in  its  feeding  habits.  When  once  it  starts 
to  feed  it  is  difficult  to  dislodge  while  other  fleas  are  correspond- 
ingly difficult  to  get  to  stay  in  one  place.  Bishopp  reports  that  as 
high  as  85  per  cent  of  the  young  chicks  have  been  killed  by  this 
flea  and  injury  to  older  fowls  is  considerable.  They  infest  first 
the  heads  and  necks  and  later  the  bodies  of  the  hosts,  being  present 
throughout  the  year. 

In  control  of  the  flea  it  is  necessary,  first  to  keep  poultry  away 
from  other  animals  which  may  act  as  carriers;  then  clean  out  the 
chicken  houses  as  for  control  of  the  mites,  soak  the  floors,  if  of 
earth,  with  salt  water  and  spray  the  house  as  for  mites,  but 
preferably  with  crude  petroleum  or  with  a  solution  of  creolin, 
Treat  all  possible  breeding  places  with  the  same  substances  and 
shut  the  chickens  out  from  those  which  it  is  impossible  to  treat. 

The  fleas  themselves  on  the  poultry  may  be  killed  by  treating 
the  infested  portions  with  carbolated  vaseline  or  with  kerosene 
and  lard.     Destroy  rats  as  these  sometimes  harbor  the  fleas. 

Other  fleas  which  some- 
times infest  poultry  may  be 
controlled  in  the  same  man- 
ner as  the  one  above    . 

A  rather  new  poultry 
pest,  found  in  the  South- 
west only,  is  the  Fowl-tick 
(Argas  miniatus  Kock). 
Chickens  may  be  killed  by 

this  pest  and    certainly  no  ^       ^„       ^,     .     ,    .  ,        ,  ,    . 
..,,,.,  ,/  .        Fig.  604.— The  fowl  tick:  adult  female, 

mfested  chicken  can  thrive,      upper  and  lower  sides.     Greatly  en- 

The  appearance  of  the  tick     1^"  a^"     ^^^°™  Bishopp,  U.  S.  Dept. 

is  not  different  from    other 

ticks  and  large  mites.      Young  remain  attached  to  the  hosts  for 

several  days  but  the  older  ticks  feed  at  night  only,  hiding  in  cracks 

during  the  day  as  do  the  mites.      Treating  the  house  with  crude 


688  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

petroleum  as  for  mites,  is  said  to  be  more  effective  and  satisfac- 
tory as  a  means  of  control  than  destruction  of  the  pests  once 
they  are  established.  Proper  sanitary  and  local  quarantine  meas- 
ures should  be  devised  for  this  purpose,  the  object  in  general 
being  to  start  business  in  uninfested  quarters  and  by  rigid  inspec- 
tion and  quarantine,  to  keep  out  all  infested  fowls. 


BIBLIOGRAPHY 

An  extended  bibliography,  to  do  so  much  as  approximate 
completeness,  would  occupy  much  more  space  than  can  be 
devoted  to  it  here.  We  therefore  Ust  only  a  few  titles  and 
indicate  the  general  sources  of  information. 

1.  PubHcations  of  the  United  States  Department  of  Agricul- 
ture: 

a.  Farmers'    Bulletins.     Sent   free   upon    application. 

Over  1100  titles  have  been  issued  and  a  great 
proportion  of  these  deal  with  entomology  in  its 
economic  aspect. 

b.  Department  Bulletins.    Nearly  a  thousand  of  these 

have  been  issued  in  the  last  seven  years.  They 
deal  with  problems  in  a  somewhat  more  scientific 
and  detailed  manner  than  do  the  Farmers' 
Bulletins.  A  goodly  number  of  them  are  upon 
entomological  subjects. 

c.  Bulletins  of  the  Bureau  of  Entomology.      About 

130  of  these  were  issued.  They  deal  with  a  wide 
range  of  subjects  in  the  field  of  economic  ento- 
mology. 

d.  Circulars  from  the  Bureau  of  Entomology.    About 

175  of  these  were  issued.  They  contain  brief 
popular  accounts  of  many  of  the  common  insects. 

e.  The  Journal    of    Agricultural    Research.     In    this 

journal  are  published  the  results  of  original  in- 
vestigations. Much  excellent  work  on  insects 
has  been  published  in  this  journal.  The  indi- 
vidual papers  are  usually  obtainable  as  separates. 

Many  of  these  publications  are  to  be  obtained  free  from 
the  Department  of  Agriculture.     Others  may  be  purchased 

689 


690  BIBLIOGRAPHY 

at  small  cost  from  The  Superintendent  of  Documents,  Wash- 
ington, D.  C.  Some  titles  are  out  of  print,  but  such  papers 
are  usually  obtainable  in  revised  form  in  later  publications. 
A  very  excellent  library  of  entomology  might  be  formed 
entirely  of  publications  in  the  several  series  listed  above. 

2.  Pubhcations  of  the  various  state  agricultural  experiment 

stations. 

Each  one  of  the  several  states  maintains  one  or  more 
experiment  stations.  These  issue  bulletins  from  time  to  time 
and  much  of  the  best  information  available  on  injurious 
insects  is  contained  in  these  bulletins.  Subjects  of  local 
interest  are  likely  to  be  more  fully  treated  in  the  state  bulletins. 

These  bulletins  may  always  be  obtained  free  upon  apphca- 
cation  so  long  as  the  supply  lasts. 

3.  State  pubhcations  issued  by  agencies  other  than  the  State 

Agricultural  Experiment  Stations.  This  will  include  the 
State  Departments  of  Agriculture  which  issue  reports 
from  the  state  entomologists.  Much  valuable  informa- 
tion will  be  found  in  these  reports  which  is  not  available 
elsewhere.  Especially  extensive  reports  of  this  nature 
are  issued  by  the  State  Entomologists  of  New  York, 
Ilhnois,  Minnesota,  Missouri  and  Indiana. 

Other  state  agencies  issuing  publications  which  include 
entomological  subjects  are  State  Horticultural  Boards  or  Com- 
missions, as  in  Florida  and  Cahfornia,  State  Entomological 
Commissions  and  State  Educational  Departments. 

State  pubhcations  can  usually  be  secured  free  upon  appli- 
cation. 

4.  The  Journal  of  Economic  Entomology. 

Much  of  the  newest  work  in  economic  entomology  is 
reported  first  in  this  journal  and  many  articles  are  available 
there  only.  It  issues  six  numbers  annually  and  the  subscrip- 
tion price  is  low.  It  may  be  obtained  through  Mr.  A.  F. 
Burgess,  Melrose  Highlands,  Mass. 

5  General  texts. 

Fundamental  information  on  entomology  is  obtained  best 
from  some  one  of  the  standard  texts,  of  which  there  are  sev- 


BIBLIOGRAPHY  691 

eral,  adapted  more  or  less  to  the  varjdng  needs  of  students. 
Some  titles  follow: 

Manual  for  the  Study  of  Insects,  Comstock.  J.  H.  &  A.  B. 

Comstock  Publishing  Co.,  Ithaca,  N.  Y. 
American  Insects,  Kellogg,  V.  L.    Doubleday,  Page  and  Co. 
School  Entomology,  Sanderson,  E.  D.,  and  Peairs,  L.  M. 

John  Wiley  and  Sons,  Inc.,  N.  Y. 
Agricultural  Entomology,  Osborn,  H.  F.     Lippincott. 
Economic  Entomology,  Smith,  J.  B.     Lippincott. 
Injurious  Insects,  O'Kane,  W.  C.     Macmillan. 
Elementary  Entomology,  Sanderson,  E.  D.,  and  Jackson, 

C.  F.     Ginn  and  Co. 
Manual  of  Vegetable  Garden  Insects,  Crosby,  C.  R.,  and 

Leonard,  M.  D.     Macmillan. 
Manual  of  Fruit  Insects,  SUngerland,  M.  V.,  and  Crosby, 

C.  R.     Macmillan. 
Medical  and  Veterinary  Entomology,  Herms,  W.  B.     Mac- 
millan. 
Handbook   of   Medical   Entomology,    Riley,    W.    A.,    and 

Johannsen,  0.  A.     Comstock  Publishing  Co. 
Fumigation  Methods,  Johnson,  W.  G.     The  Orange-Judd 

Co. 

The  above  is  a  partial  list.  There  are  hundreds  of  other 
publications  which  will  be  of  help  to  the  student  when  they 
chance  to  be  available. 


INDEX 


Acanthiida?,  647 

Acarina,  254,  563,  626,  649,  670,  683 
Achemon  sphinx,  461 
Acrididaj,  95 
Adalia  bipunctata,  9 
Adhesives,  58 
Adoxus  vitis,  443 
Aedes  calopus,  642 
iEgerita  webberi,  611 
Agallia  sanguinolenta,  268 
Agrilus  ruficollis,  409 
Agriotes  mancus,  81 
Agromyza  simplex,  382 
Agromyzidse,  382,  606 
Agrotis  annexa,  88 
messoria,  85 
ypsilon,  85 
Air-slaked  lime,  283 
Alabama  argillacea,  228 
Aleurocanthus  woglumi,  633 
Aleurodidae,  610 
Aleurothrixus  howardi,  611 
Alfalfa  caterpillar,  209 
looper,  211 
weevil,  195 
Alsophila  pometaria,  501 
American  acridium,  100 

frit  fly,  132 

roach,  652 

syrphus-fly,  12 
Ampeloglypter  ater,  447 
Amphicerus  bicaudatus,  449 

punctipennis,  451 
Anarsia  lineatella,  580 
Anasa  tristis,  348 
Ancylis  comptana,  396 
Angoumois  grain  moth,  182 
Anopheles,  640 


Ant,  Argentine,  608,  652 
corn-field,  152 
little  black,  652 
little  red,  652 
pavement,  652 
Ant  syrup,  608 
Ants,  house,  652 
Ants,  white,  655 
Anthomyia  egg  parasite,  103 
Anthomyiida;,  291,  311,  314,  374,  411 
Anthonomus  grandis,  243 

grandis  thurberia;,  244 
quadrigibbus,  561 
signatus,  400 
Anthrenus  scrophularise,  653 
Apanteles  congregatus,  220 
glomeratus,  323 
Aphidida;,    135,    149,  226,  289,  299, 
333,  344,  389,  423,  432,  514,  528, 
586,  592 
Aphidius,  136,  295 

avenaphis,  136 
Aphis  avenae,  535 
brassicae,  333 
fitchii,  535 
forbesi,  389 
gossypii,  226,  344,  629 
maidi-radicis,  149 
maidis,  155 
medicaginis,  226 
persicae-niger,  586 
pomi,  12,  528 
pseudo-brassicae,  336 
pyri,  532 
rumicis,  289 
setariae,  594 
sorbi,  532 


694 


INDEX 


Aphis,  apple,  528 

black  peach,  585 
cabbage,  333 
corn-root,  149 
currant,  425 
English  grain,  135 
European  grain,  535 
green  peach,  587 
melon,  344 
pea,  293 
rosy  apple,  532 
spinach,  335 
spring  grain,  137 
woolly,  514 
Aphis  lions,  347 
Apple  aphis,  528 

rosy,  532 
woolly,  514 
caterpillar,  red-humped,  544 

yellow-necked,  542 
curcuho,  561 
leafhopper,  273 
leaf  miner,  545 
maggot,  559 
plant  lice,  528 
Apple-tree  borer,  flat  headed,  524 

round  headed,  520 
tent  caterpillar,  16,  538 
worm,  552 
worm,  lesser,  553 
Apple  twig  borer,  449 
Application  of  insecticides,  56 
Arctiidffi,  232,  485 
Argas  miniatus,  687 
Argentine  ant,  608 
Arizona  wild  cotton  weevil,  244 
Armored  scales,  599 
Army  worm,  110 

beet,  302 
fall,  114 
Arsenate  of  calcium,  42 

lead,  powdered,  40,  41 
Arsenic,  white,  43 
Arsenical  dips,  679 


Arsenite  of  lead,  41 

lime,  41 

sodium,  43 

zinc,  43 
Aschersonia  aleyrodes,  612 

flavocitrinis,  612 
Ash-gray  blister  beetle,  311 
Asparagus  beetle,  378 

twelve  spotted,  381 

miner,  382 
Asphalt  paint,  53 
Asphaltum,  53,  523 
Aspidiotus  camellije,  601 

hederae,  602 

perniciosus,  470 

rapax,  601 
Assassin  bugs,  623 
Atomizers,  59 
Attagenus  piceus,  653 
Aulacizes  irrorata,  234 
Australian  roach,  652 
Autographa  brassicae,  327 
calif ornica,  211 
simplex,  368 

Babesia  bigemina,  675 
Bagworm,  503 
Banded  flea-beetle,  363 
Banding  material,  609 
Bark-beetle,  fruit  tree,  475 

peach  tree,  582 
Barred  winged  onion  maggot,  378 
Barrel  pumps,  62 
Batrachedra  rileya,  181 
Bean  aphis,  289 

ladybird,  287 

leaf-beetle,  285 

weevil,  281 

European,  285 
four-spotted,  284 
Bedbugs,  647 
Bee-flies,  104 
Beet  aphis,  299 

army  worm,  302 

leaf  beetle,  305 
leafhopper  307 


INDEX 


695 


Beet  leaf  miner,  311 

root  aphis,  300 
Bembecia  inarginata,  403 
Bibliography,  689 
Bill  bugs,  160 

maize,  162 
Biting  lice,  667 
Black  carpet  beetle,  653 

cherry  louse,  595 
Black-fly,  633 
"Black  Leaf  40",  51 
Black  peach  aphis,  585 

scale,  602 

scale  fungus,  620 
Blackberry  gall  maker,  411 
Blatta  orientalis,  652 
Blatella  germanica,  652 
Blattidse,  650 
Blissus  leucopterus,  90 
Blister  beetle,  ash  gray,  288,  311 
Nuttall's,  288 
striped,  310 
Blister  beetles,  104,  270,  288,  310 
Blister  mite,  363 
Body  louse,  649 

of  chickens,  681 
Book  lice,  655 
Boll  weevil,  243 
worm,  168 
Bordeaux  mixture,  53 

nozzle,  70 
Borer,  cotton  square,  232 

flat  headed,  524 

grapecane,  449 

peach  tree,  575 

peach  twig,  580 

round  headed,  520 
Botflies,  661 
Bottle  flies,  640 
Brachymena  4-pustulata,  23 
Bracon  mellitor,  251 
Braconidae,  16,  137 
Bran  mash,  57 
Brown  fungus,  67 

-tail  moth,  489 
Bruchida?,  278 
Brucophagus  funebris,  202 


Bruchus  chinensis,  284 

obtectus,  281 

quadriniaculatus,  284 

pisorum,  278 

rufimanus,  285 
Bryobia  pratensig,  198 
Bucket  pumps,  59 
Bud  moth,  549 
Bud  worms,  221 
Buff'alo  moth,  652 
Buff'alo  tree-hopper,  478 
Buhach,  50 
Buprestida;,  409,  524 
Byturus  unicolor,  416 

Cabbage  aphis,  333 

bug.  Harlequin,  330 

butterfly,  321 

Southern,  326 

looper,  327 

maggot,  314 

plutella,  328 

worm,  imported,  321 
Cadelle,  179 
Calandra  granaria,  176 

oryzae,  176 
Calandrida;,  160,  176 
Calico-back,  330 
California  peach-borer,  575 

red  scale,  599 
Caliroa  cerasi,  569 
Calocoris  rapidus,  235 
Calosoma  calidum,  14 
scrutator,  14 
sycophanta,  498 
Cambala  annulata,  270 
Camnula  pellucida,  99 
Canker  worm,  fall,  501 

spring,  499 
Canker  worms,  498 
Cantharis  nuttalli,  288 
Capsida;,  235,  422,  571 
Carbolic  acid  emulsion,  52 
Carbolineum,  477 
Carbon  bisulphide,  53,  186,  320 
Carpocapsa  pomonella,  552 


696 


INDEX 


Carrot  beetle,  369 

rust  fly,  370 
Case-bearers,  547 
Case-making  moth,  654 
Cassida  bivittata  385 
Cassidse,  384 
Cat  and  dog  flea,  646 
Cathartus  advense,  179 

gemellatus,  178 
Cattle  scab,  670 
ticks,  672 
Carpet  beetles,  653 
Ceratitis  capitata,  633 
Ceroplastes  floridensis,  604 
Cecidomyiidse,  117,  133,  200 
Celery  caterpillar,  366 

looper,  368 
Cephidse,  128 
Cephus  occidentals,  128 

pygmgeus,  129 
Cerambycidae,  405,  520 
Ceratoma  trifurcata,  285 
Ceresa  bubalis,  478 
Chaetocnema  confinis,  383 
Chaetopsis  senea,  378 
Chaff  scale,  602 
Chalcididaj,  122,  202 
Chalcis  flies,  17 
Cherry  fruit  fly,  596 

louse,  black,  595 
Chicken  lice,  681 

mites,  683 
Chiggers,  649 
Chilocorus  bivulnerus,  11 
Chin-fly,  661 
Chinch  bug,  90 
Chionaspis  citri,  602 

furfura,  527 
Chiropachis  colon,  476 
Chloridea  obsoleta,  168,  221,  238 

virescens,  221 
Chrysobothris  femorata,  524 
Chrysomelidffi,    143,   212,   260,   266, 

271,  285,  304,  338,  361,  378,  383, 

393,  441,  629 


Chrysomphalus  aonidum,  602 
aurantii,  599 

citrinus,  600 
Chrysomyia  macellaria,  660 
Chrysopidae,  137,  295,  347,  623 
Cicada,  26,  479 

septendecem,  479 
Cicadidae,  479 
Cigar  case-bearer,  547 
Cigarette  beetle,  224 
Cimicidae,  647 
Cimex  lectularius,  647 
Cirphus  unipuncta,  110 
Citrus  insects,  599 

mealy  bug,  606 

thrips,  622 
Clayton  gas,  55 
Clothes  moths,  654 
Cloudy-winged  whitefly,  610 
Clover  insects,  189 

hay-worm,  206 

leafhopper,  208 

leaf  weevil,  192 

mite,  198 

root-borer,  189 

root  curculio,  192 

seed  caterpillar,  203 

seed  chalcid,  202 

seed  midge,  200 
Cluster-fly,  640 
Cnemidocoptes  Isevis  gallinae,  684 

mutans,  685 
Coccidae,  470,  525,  583,  599 
Coccinella  novem-notata,  8,  347 
Coccinellidse,  8,  137,  287,  295,  351 
Coccotorus  scutellaris,  590 
Coccus  hesperidum,  603 
Codling  moth,  552 
Collinus  meromyzae,  133 
Colaspis  brunnea,  393 
Cold  storage,  655 
Coleophora  fletcherella,  547 
malivorella,  547 
Colorado  potato  beetle,  260 
Compressed  air  spayers,  61 
Conotrachelus  nenuphar,  505 
Contact  insecticides,  39,  44 


INDEX 


697 


Convergent  lady-bug,  10,  266 
Cooties,  649 
Coptocycla  bicolor,  385 
Coreidae,  236,  348 
Corn-borer,  European,  173 
Corn  ear  worm,  21,  168 
Corn  leaf  aphis,  155 
root  aphis,  149 

webworm,  146 
worm,  southern,  144 
western,  143 
stalk  borer,  larger,  16 
lesser,  167 
wireworm,  81 
Cornfield  ant,  152 
Corrodentia,  655 
Cotton  boll  cutworm,  241 
weevil,  243 
bollworm,  238 
caterpillars,  232 
dusting,  231 
leaf-bug,  235 
stainer,  237,  631 
worm,  228 

egg-parasite,  230 
square  borer,  232 
Cottony-cushion  scale,  604 
Cottony  maple  scale,  605 
Cow-pea  weevil,  284 
Crambidae,  146,  158,  213 
Crambus  caliginosellus,  146,  213 
Craponius  inaequalis,  466 
Criddle  mixture,  110 
Cricoceris  asparagi,  378 

12-punctata,  381 
Crop  rotation,  30 
Crude  petroleum,  45 
Ctenocephalus  canis,  646 
Cucujdae,  177 

Cucumber  beetle,  spotted,  343 
striped,  340 
flea-beetle,  267 
Culex,  640 
Culex  pipiens,  640 

sollicitans,  644 
Culicidie,  641 


Curculio,  apple,  561 

clover  root,  192 
grape,  466 
plum,  505 
Curculionidae,  192,  195,  243,  256,365, 
391,  400,  447,  466,  505,  561,   590 
Curly-leaf,  beet,  307 
Currant  aphis,  425 

borer,  imported,  418 
fly,  429 

span-worm,  428 
stem  girdler,  419 
worm,  imported,  426 
worm,  native,  427 
Cut-offs,  74 
Cutworm,  bronzed,  86 

cotton  boll,  241 
dark-sided,  86 
dingy,  87 
glassy,  88 
granulated,  88 
greasy,  88 
well-marked,  88 
Cutworms,  86,  300 
Cydia  pomonella,  552 
Cylas  formicarius,  386 
Cymatophora  ribearia,  428 
Cynipidae,  411 

Dactylopiinae,  606 

Dasyneura  leguminicola,  200 

Datana  ministra,  542 

Deilephila  lineata,  232,  460 

Depluming  mite,  684 

Dermacentor  venustus,  673 

Dermanyssus  gallinae,  683 

Dermestidae,  416,  652 

Desmia  funeralis,  459 

Destruction  of  weevil,  186 

Development  of  insects,  20 

Diabrotica  12-punctata,  144,  343 
longicornis,  143 
soror,  629 
vittata,  272,  340 

Dialeurodes  citri,  610 

citrifolii,  610 


698 


INDEX 


Diarftond-back  moth,  328 
Diaphania  hyalinata,  359 

nitidalis,  356 
Diastrophus  turgidus,  411 
Diatraea  zeacolella,  158 
Dictyophorus  reticulatus,  101 
Diplosis  tritici,  133 
Dipping  live  stock,  678 
Diptera,  15,  669 
Disc  nozzles,  68 
Disonycha  triangularis,  303 

xanthomelaena,  304 
Dolerus  arvensis,  129 
ajl  coUaris,  129 

Drasterius  elegans,  81 
Drepressaria  heraclina,  371 
Drone-fly,  11 
Dusting  apparatus,  75 

mixtures,  77 
Dyadercus  suturellus,  237,  631 

Earworm,  168 

Echidnophaga  gallinacea,  687 
Egg-plant  flea-beetle,  267 
Elachistidse,  181,  547 
Elasmopalpus  lignosellus,  167 
Elateridae,  80 
Empoasca  mali,  273 
Empusa  aphidis,  295 

sphaeroperma,  194 
Enarmonia  interstictiana,  203 

prunivora,  553 
English  grain-louse,  135 
Ephestia  kuehniella,  179 
Epicauta  vittata,  105,  310 
Epidaphus  scabei,  269 
Epilachna  borealis,  351 

varivestris,  287 
Epitrix  cucumeris,  267 
fuscula,  267 
parvula,  212,  267 
Epochra  canadensis,  429 
Eriophyes  oleiverus,  626 

>  -      pyri,  563 
Eriophyidae,  563,  627 
Eriosoma  lanigera,  514 
Eristalis  tenax,  11 


Estigmene  acraea,  232 
Eulecanium  nigrofasciatum,  683 
Euproctis  chrysorrhcea,  489 
European  bean-weevil,  285 
corn-borer,  173 
grain-aphis,  535 
Eurymus  eurytheme,  209 
Euschistus  punctipes,  215 
Eutettix  tenella,  307 
Euthrips  nicotaniae,  225 
Evergreen  bagworm,  16,  503 
Exorista  flavicauda,  104 
leucaniae,  104 

Fall  army-worm,  1 14 

Fall  canker  worm,  501 

Fall  webworm,  485 

Fannia  brevis,  640 

Farm  methods,  29 

Feltia  subgothica,  87 

Fidia  cana,  442 

viticida,  441 

Fiery  ground  beetle,  13 

Fire-bug,  330 

Fishmoth,  655 

Flea,  cat  and  dog,  646 

chicken  stick  tight,  687 
human,  645 

Fleabeetle,  banded,  363 

cucumber,  267 
egg-plant,  267 
grapevine,  451 
pale  striped,  361 
potato,  267 
spinach,  304 
sweet  potato,  383 
tobacco,  212,  267 

Fleabeetles,  266,  303,  338 

Fleas,  645,  687 

Flesh-fly,  104 

Florida  flower  thrips,  620,  625 
red  scale,  602 

Flour  moths,  179 

Fly-free  datas,  120 

Fly  nets,  660 

Fly-traps,  638 

Formicidae,  652 


INDEX 


699 


Four-lined  leaf-bug,  422 
Four-spotted  bean  weevil,  284 
Fowl-tick,  687 

Frankiniella  bispinosus,  622,  625 
Fruitfly,  cherry,  596 

Mediterranean,  632 
Fruit  moth,  510 
Fruit-tree  bark-beetle,  475 
Fumigation,  54,  281,  621 
Fusarium,  612 

Garden  webworm,  211,  232,  363 
Gas  tar,  82 
Gases,  39,  53 

Gastrophius  haemorrhoidalis,  661 
intestinalis,  661 
nasalis,  661 
Gelechiidae,  182,  253,  580 
Geometridai,  428,  498 
German  grain-aphis,  135 

roach,  652 
Girdler,  grapecane,  447 
Glassy  cutworm,  88 
Glassy-winged  sharpshooter,  234 
Gold-bugs,  384 
Grain-beetle,  foreign,  177 

red-necked,  177 
saw-toothed,  177 
Grain  weevils,  176 
Granary  weevil,  176 
Grape-berry  moth,  462 
cane  borer,  449 
cane  girdler,  447 
curculio,  466 
leaf-hopper,  458,  459 
root-worm,  441 
Grapevine  flea-beetle,  451 
phylloxera,  432 
root-borer,  436 
GraphoHthidaj,  203 
Graphops  pubescens,  393 
Grass  saw-fly,  129 

worm,  114 
Grasshoppers,  95 
Graybacks,  649 
Greedy  scale,  601 


Green-bug,  137 

Green  clover-worm,  211 

peach-aphis,  335,  587 

soldier-bug,  236,  590 
Ground  beetles,  13 
Ground  beetle,  fiery,  13 

murky,  13 
Gryllida;,  407 

Gryptochajtiim  monophlccbi,  606 
Gymnonychus  appendiculatus,  427 
Gypsy  moth,  492 

Hadena  devastatrix,  88 
Hajmatobia  serrata,  658 
Hffimatopinus  eurysternus,  668 

pedalis,  668 

suis,  668 

vituli,  668 
Haltica  chalybea,  451 
Harlequin  cabbage-bug,  330 
Harmolita  grandis,  124 

tritici,  122 
Harpalus  caliginosus,  15,  264 
Harpiphorus  maculatus,  395 
Hawk-moths,  461 
Head  louse,  649 

chicken,  680 
Heat,  188 
Hellebore,  43 
Hemispherical  scale,  604 
Hessian-fly,  117 
Hippoboscidae,  669 
Hippodamia  convergens,  10,  266,  357 
Hog-louse,  668 
Homalodisa  triquetra,  234 
Hop  plant-louse,  593 
Hopperdozers,  107 
Hopperette,  308 
Horizontal  pumps,  66 
Horn-fly,  658 
Hornworms,  216 
Horse  bots,  661 
Horse  flies,  659 
Horse  scab,  672 
House  ants,  652 

centipede,  655 
mosquito,  644 


700 


INDEX 


Housefly,  635 
Household  insects,  635 
Human  flea,  645 
Hyalopterus  arundinis,  592 
Hyalastinus  obscurus,  189 
Hydrocyanic  acid  gas,  54,  187,  622 
Hydrometers,  49 
Hymenoptera,  15 
Hymenopterous  parasites,  15 
Hyphantria  cunea,  485 

textor,  489 
HjTDoderma  bovis,  666 

lineata,  664 
Hypsopygia  costalis,  206 

Icerya  purchasi,  604 

Ichneumon  flies,  15 

Ichneumonidse,  545 

Imported  cabbage  worm,  321 
currant  borer,  418 
worm,  426 
grape  root-worm,  443 
onion  maggot,  374 

Iiidian-meal  moth,  180 

Injury  by  insects,  1 

Insect  parasites,  15 

Insecticides,  39 

application  of,  56 
contact,  39 

Internal  anatomy  of  insects.  28 

Iridomyrmex  humilis,  608,  631 

Janus  integer,  419 

Jassidaj,  208,  234,  273,  307,  456 

Joint-worm,  121 

Kainit,  149 

Kedzie  formula,  43 

Kerosene,  45 

emulsion,  44 
Knapsack  pumps,  60 

Lace-wing  flies,  295,  623 
Lachnosterna,  genus,  78 

arcuata,  79 
Lady-bird,  bean,  287 
Lady-bird,  convergent,  347 

nine-spotted,  347 

spotted,  347 

squash,  351 


Lady-bugs,  8 

vedalia,  605 
Laphygma  exjgua,  302 

frugiperda,  114 
Larger  corn-stalk  borer,  158 
Lasiocampidffi,  538 
Lasioderma  serricome,  224 
Lasius  niger,  152 
Lasius  niger,  americanus,  152 
Laspeyresia  molesta,  510 
Leaf-bug,  four-liHed,  402 
Leaf-folder,  grape,  459 
Leaf-footed  bugs,  236 
Leaf-hopper,  apple,  273 
grape,  456 
Leaf-miner,  apple,  645 
beet,  311 
spinach,  311 
Lebia  grandis,  14 
Lema  trihneata,  271 
Lepidosaphes  beckii,  599 
gloveri,  601 
ulmi,  525 
Lepisma  domestica,  655 
saccharalis,  655 
Leptinotarsa  decemlineata,  260 
Leptoglossus  oppositus,  236 
Leptus  americanus  irritans,  650 
Lesser  apple  worm,  555 

corn-stalk  borer,  167 
peach-tree  borer,  575 
Leucopermes  flavipes,  655 
Lice,  648 

on  live  stock,  667 
poultry,  680 
Light  traps,  37 
Ligyrus  gibbosus,  369 
Lime-sulphur  wash,  46 

dilution  table,  48 
Geneva  formula, 
47 

self-boiled,  49 
Limneria  aedemesia,  545 

fugitiva,  545 
Liparida),  489 
Lipeurus  heterographicus,  680 


INDEX 


701 


Little  black  ant,  652 
house-fly,  640 
red  ant,  652 
Lixus  concavus,  365 
Locust,  California  devastating,  99 

differential,  101 

lesser  migratory,  98 

pellucid,  99 

red-legged,  99 

Rocky  Mt.,  95 

two-striped,  100 
London  purple,  40 
Long-nosed  hog  louse,  668 
Long-nosed  ox  louse,  668 
Long  scale,  601 
Loxostege  similalis,  232,  363 

sticticalis,  301 
Lubber  grasshopper,  101 
Lycaenidae,  232 
Lydella  doryphorae,  262 
Lygaeidse,  90 
Lygus  pratensis,  571 
Lysiphlebus  testaceipes,  140,  347 

Macrobasis  unicolor,  288,  311 
Macrodactylus  subspinosus,  454 
Macrosiphum  cerealis,  135 
granaria,  135 
pisi,  293 
solanifolii,  272 
Maize  bill-rug,  163 
Malacosoma  americana,  16,  538 
Malaria,  641 
Mallophaga,  667,  680 
Mange,  horse,  672 
swine,  672 
Margaropus  annulatus,  673 
Mayetiola  destructor,  117 
Meal  moths,  179 

snout-moth,  181 
Mealy  bugs,  606 

plum-louse,  592 
Mediterranean  flour  moth,  179 

fruit-fly,  632 
Megilla  maculata,  10,  347 
Melanoplus  atlantis,  99 

bivittatus,  100 


Melanoplus  devastator,  99 

differentialis,  101 
femur-rubrum,  99 
spretus,  95 
Melanotus  cribulosus,  81 
Melittia  satyriniformis,  353 
Meloida;,  270,  310 
Melon  aphis,  344,  629 
caterpillar,  359 
Melophagus  ovinus,  669 
Membracidse,  478 
Memythrus  polistiformis,  436 
Menopon  biseriatum,  681 

pallidum,  681 
MeromyzsB  americana,  129 
Metamorphosis  of  insects,  20 
Meteorus  hypantriae,  488 
Mexican  cotton  boll-weevil,  243 

orange  maggot,  632 
Microcera,  612 

fujikuroi,  620 
Microgaster,  16 
Microweisea  misella,  476 
Millipedes,  270 
Miscible  oils,  46,  620 
Mite,  clover,  198 

depluming,  684 
poultry,  683 
rust,  626 
scab,  676 
silver,  626 
Monomorium  minimum,  652 
pharaonis,  652 
Monophadnis  rubi,  413 
Monoxia  puncticoUis,  305 
Mosquitoes,  641 
Mouth-parts,  25 
Murgantia  histrionica,  330 
Murky  ground  beetle,  14,  264 
Musca  domestica,  635 
Muscardine  fungus,  95 
Muscida;,  635,  657,  660 
Myriangium  duriaei,  620 
Myzus  cerasi,  595 

persicae,  335,  587 
ribis,  425 


702 


INDEX 


Nephelodes  minians,  86 
Nezara  hilaris,  236,  590 

viridula,  590,  630 
Nico-fume,  51 
Nicotine-lime  spray,  537 
Nine-spotted  lady-bird,  8 
Noctua  clandestina,  87 
Noctuida?,  82,  86,  110,  114,  168,  211, 

221,  228,  238,  241,  302,  327,  368 
Nose-fly,  661 
Notodontidae,  542 
Nozzles,  68 
Novius  cardinalis,  665 

Oberea  bimaculata,  405 
(Ecanthus  nigricornis,  407 

niveus,  407 
(Ecophoridae,  371 
(Estridae,  661 
(Estris  ovis,  666 
Oil  emulsions,  615 
Oncemetopia  lateralis,  234 
undata,  234 
Onion  maggot,  barred  winged,  378 
imported,  374 
thrips,  372 
Ophion  macrurum,  16 
Orange  dog,  629 

maggot,  632 
scale,  599 
Orchard  dusting,  75 
Oriental  peach  moth,  510 
roach,  652 
Oscinus  variabilis,  132 
Ox-louse,  long  nosed,  668 
short  nosed,  668 
Ox-warble,  664 
Oyster-shell  scale,  525 

Pachynematus  extensicornis,  129 
Paleacrita  vernata,  499 
Pale-striped  flea-beetle,  361 
Papaipema  nitella,  82 
Papilio  cresphontes,  629 

polyxenes,  366 
Papilionidse,  366,  629 
Parajulus  impressus,  270 


Paris  green,  39 
Parlatoria  pergandii,  602 
Parsnip  web  worm,  371 
Pavement  ant,  652 
Pea  aphis,  293 
moth,  297 
weevil,  278 
Peach  lecanium,  583 

tree  bark  betle,  582 

borer,  575 
twig  borer,  580 
Pear  leaf  blister-mite,  563 
psylla,  566 
slug,  569 
thrips,  568 
Pectinophora  gossypiella,  253 
Pedicuhdae,  648,  668 
Pediculus  capitis,  649 

vestmenti,  649 
Pegomjria  ceparum,  374 
fusciceps,  291 
vicina,  311 
Pemphigus  betse,  299 
Pentarthron  minutem,  228 
Pentatomidae,  215,  236,  330,  630 
Peridroma  saucia,  85 
Periodical  cicada,  479 
Periplaneta  americana,  652 
australasise,  552 
Persian  insect  powder,  50 
Petroleum,  45 

Phlegethontius       quinquemaculatus, 
216 
sexta,  216 
Phorhia  brassicae,  314 
Phorodon  humuli,  593 
PhlcEthribus  liminaris,  582 
Pholus  achemon,  461 
Phorbia  rubivora,  411 
Phthirius  inguinalis,  649 
Phthorimaea  operculella,  223,  258 
Phyllotreta  pusilla,  338 
sinuata,  338 
vittata,  303,  338 
Phylloxera,  grapevine,  432 
Phylloxera  vastatrix,  432 


INDEX 


703 


Phytonomus  posticus,  195 

punctatus,  192 
Pickle  worm,  358 
Pieridac,  209,  321 
Pimpia  conquisitor,  230 

inquisitor,  15 
Pink  boUworm,  253 
corn-worn|^  181 
scale  fungus,  620 
Pipiza  radicans,  12 
Pistol  case-bearer,  547 
Pithy  gall,  411 
Plant  bug,  southern  green,  590 

tarnished,  571 
Plant-bugs,  236 
Plant  lice,  apple,  528 
cotton,  226 
louse,  hop,  593 
Plathypena  scabra,  211 
Plodia  interpunctella,  180 
Plum  aphids,  592 
curculio,  505 
gouger,  590 
louse,  mealy,  592 

rustj^-brown,  594 
Plutella  maculipennis,  328 
Podisus  spinosus,  261 
Poeciliocapsus  lineatus,  422 
Poisioned  baits,  57 
Pollenia  rudis,  640 
Polychrosis  viteana,  462 
Pontia  napi,  326 

protodice,  326 
rapae,  321 
Porthetria  dispar,  492 
Potato  aphids,  272 

beetle,  Colorado,  260 

three-lined,  271 
flea-beetle,  267 
scab  and  insects,  269 
stalk-borer,  256 
tuber-worm,  258 
Potherb  butterfly,  326 
Poultry  lice,  680 

mites,  683 
Power  sprayers,  67 
Proctotrjrpidae,  17 


Prodenia  ornithogallis,  241 

Pseudococcus  calceolaria;,  631 
citri,  606 

Psila  Tosx,  370 

Psilidaj,  370 

Psoroptes  communis  bovis,  670 
equi,  671 
ovis,  671 

Psychidae,  503 

Psylla  p3Ti,  566 

Psyllida?,  566 

Pteromalus  puparum,  322 

Pteronus  ribesii,  426 

Ptinida;,  224,  449 

Pubic  louse,  649 

Pulex  irritans,  545 

Pulvinaria  innumerabilis,  605 

Pumpkin  bugs,  236,  630 

Purple  scale,  599 

Pyralidida;,  167,  173,  180,  206,  232, 
459 

Pyralis  farinalis,  181 

Pyrausta  nubialis,  173 

Pyraustidae,  173,  301,  356,  363 

Pyrethrum  50 

Pyrrochoridse,  237 

Railroad  worm,  559 
Raspberry  bytutus,  416 

cane-borer,  405 
cane  maggot,  411 
root  borer,  403 
sawfly,  413 
Rat  flea,  645 
Red-bugs,  237 
Red  fungus,  612 

-headed  scale  fimgus  620 
-humped  apple  caterpillar,  544 
-necked  cane  borer,  409 
spider,  254,  627 
-tailed  tachina-fly,  113 
-weevil,  133 
Repellants,  39.  52 
Rhagoletis  cingulata,  596 
Rhagoletis  pomonella,  559 
Rhopalosiphum  dianthi,  588 
padi,  535 


704 


INDEX 


Rhopalosiphum  prunifolise,  535 

ribis,  425 
Rhubarb  curculio,  365 
Rice  weevil,  176 
Roaches,  650 
Roach-traps,  651 
Rocky  Mt.  locust,  95 

spotted-fever  tick,  673 
Rods,  extension,  73 
Root-borer,  grapevine,  436 
Root-louse  syrphus-fly,  12 
Root  worm,  grape,  441 
Rose  chafer,  454 

Round-headed  apple  tree  borer,  520 
Round  scale,  602 
Rosy  apple  aphis,  532 
Rust  mite,  626 
Rusty-brown  plum  louse,  594 

Saissetia  hemispherica,  604 

olese,  602 
Salt-marsh  caterpillar,  232 
mosquito,  644 
San  Jose  scale,  470,  602 
Sanninoidea  exitiosa,  575 

opalescens,  575 
Saperda  Candida,  520 
Sarcophaga  carnaria,  104 
Sarcoptes  scabei,  672 
Sawfly,  raspberry,  413 
strawberry,  395 
wheat,  128 
Saw-toothed  grain  beetle,  177 
Scabs,  670 
Scab-mites,  670 
Scale  insects,  citrus,  599 
Scale,  black,  602 

California  red,  599 

chaff,  602 

cottony-cushion,  604 

Florida  red,  602 

greedy,  601 

hemispherical,  604 

long,  601 

orange,  599 

oyster-shell,  525 

purple,  599 


Scale,  round,  602 

San  Jose,  470,  602 

scurfy,  527 

snow,  602 

soft-brown,  603 

terrapin,  583 

turtle-back,  583 

yellow,  600 

wax,  604 
Scales,  armored,  599 

unarmored,  602 
Scarabseidaj,  78,  369,  454 
Scenopinus  fenestralis,  640 
Schistocerca  americana,  100 
Schizura  concinna,  544 
Sciara,  269 
Scirtothrips,  622 
Scolytidae,  189,  475,  582 
Scolytus  rugulosus,  475 
Screw-worm  fly,  660 
Scurfy  scale,  521 
Scutigera  forceps,  655 
Searcher,  14 
Seed  corn  maggot,  291 
Semasia  nigricana,  297 
Sesia  tipuliformis,  418 
Sesiida;,  353,  403,  418,  436,  575 
Seventeen-year  locust,  479 
Shaft  louse,  681 
Sharpshooters,  234 
Sheep  grub,  666 

tick,  669 
Short-nosed  ox-louse,  668 
Shot-hole  borer,  475 
Silvanus  surinamensis,  177 
Silverfish,  655 
Silver-mite,  626 
Siphonaptera,  645,  687 
Siphunculata,  648,  667,  680 
Sitones  hispidulus,  192 
Sitotroga  cerealella,  182 
Snow  scale,  602 
Soaps,  46,  51 
Sodium  arsenite,  43 
fluoride,  682 
Soft-brown  scale,  603 


INDEX 


705 


Soldier-bug,  Southern  green,  630 

spined,  261 
Solenopsis  geminata,  250 
Solid  stream  nozzle,  70 
South  African  fungus,  109 
Southern  green  plant-bug,  590 

soldier-bug,  630 
Sphaerostible  coccophila,  620 
Sphecius  spheciosus,  484 
Sphenophorus  cariosus,  162 
maidis,  163 
obscurus,  160 
ochreus,  160 
parvulus,  160 
pertinax,  162 
placidus,  162 
robustus,  163 
scoparius,  162 
sculp  tills,  162 
Spinach  aphis,  335  * 

flea-beetle,  304 
leaf-miner,  311 
Spined  soldier-bug,  262 

tobacco-bug,  215 
Sphingidae,  232,  461 
Sphinx-moths,  461 
Sporotrichum  globuliferum,  95 
Spotted  cucumber  beetle,  343 

lady-bird,  10 
Spray-guns,  71 
Spray  hose,  73 

connections,  74 
Spraying  apparatus,  59 
Spring  canker-worm,  499 
citrus  whitefly,  633 
grain-aphis,  137 
Squash  bug,  348 

ladybird,  351 
vine  borer,  353 
Stable-fly,  640,  657 
Stalk-borer,  82 
Stickers,  58 

Sticktight  flea,  chicken,  689 
Stomoxys  calcitrans,  640,  657 
Strainers,  74 

Strawberry  crown-borer,  391 
leaf-roller,  396 


Strawberry  root-louse,  389 
rootworms,  393 
sawfly,  395 
weevil,  400 
Striped  bhster  beetle,  270,  310 
cucumber  beetle,  340 
tree-cricket,  407 
turnip  flea-beetle,  338 
Structure  of  insects,  20 
Sucking  lice,  648,  667,  680 
Sugar-beet  webworm,  301 
Sulphur,  50,  188 

dioxide,  55 
fumes,  55 
-soda  spray,  624 
Sweet-potato  beetle,  two-striped,  385 
flea-beetle,  383 
root-borer,  386 
weevil,  386 
Swine  mange,  672 
Synanthedon  pictipes,  575 
Syrphidaj,  11,295,347 
Syrphus  flies,  11,  347 
Syrphus  americanus,  12 

ribesii,  11 
Syrup,  poisoned,  608 
Systaechus  oreas,  104 
Systena  blanda,  361 

hudsonias,  303 
tseniata,  303,  363 

Tabanidae,  659 
Tabanus  atratus,  660 
lineola,  660 
Tachina-flies,  104 
Taeniothrips  pyri,  568 
Tapestry  moth,  654 
Tarnished  plant  bug,  571 
Tarred  paper  cards,  320 
Tenebrioides  mauritanicus,  179 
Tenebrionidse,  179 
Tent-caterpillar,  538 
Tenthredinida?,   128,  395,  413,  419, 

426,  569 
Termites,  655 
Terrapin  bug,  330 
scale,  583 


706 


INDEX 


Tetramorium  caespitum,  652 
Tetranychidae,  198,  254 
Tetranychus  citri,  626 

mytilaspidis,  626 
sex-maculatus,  626 
telarius,  254 
Texas-fever  tick,  673 
Three-lined  leaf-beetle,  271 

potato-beetle,  271 
Thripidffi,  568 
Thrips,  citrus,  620 

florida  flower,  620,  625 
onion,  372 
pear,  568 
tobacco,  225 
tabaci,  372 
Throat  bot,  661 
Thyridopteryx  ephemerseformis,   16, 

503 
Thysanoptera,  225,  372,  568,  620 
Ticks,  672 

fowl,  687 
Tinea  biselliella,  654 
pelionella,  654 
Tineidae,  223,  258,  545,  654 
Tischeria  malifoliella,  545 
Tmetocera  ocellana,  549 
Tobacco,  51 

budworms,  221 
fleabeetle,  212,  267 
leaf-miner,  223 
split  worm,  223 
stalk- worm,  213 
thrips,  225 
worms,  216 
Tomato  fruitworm,  275 
hornworms,  275 
Tortoise  beetles,  385 
Tortricidse,  297,  396,  462,  510,  549 

552 
Towers,  sprayer,  74 
Toxoptera  graminum,  137 
Traction  sprayers,  67 
Trap-crops,  36 
Tree  crickets,  407 
Tree-hopper,  buffalo,  478 
Tree-tanglefoot,  52 


Trichobaris  trinotata,  256 
Trichodectes  parumpilosus,  667 

scalaris,  667 
Tricophaga  tapetzella,  654 
Trogositidse,  179 
Trombidium  locustarum,  103 
Trypeta  ludens,  632 
Trypetidse,  429,  559,  596 
Turnip  louse,  336 
Turtle-back  scale,  603 
Twice-stabbed  ladybird,  11 
Two-spotted  ladybird,  9 
Tychoea  brevicornis,  300 
Tyloderma  fragariae,  391 
Typhlocyba  comes,  456 
Typophorus  canellus,  393 

Uranotes  melinus,  232 

Vedalia  ladybug,  605 

Warbles,  ox,  664 
Wax  scale,  604 
Webbing  clothes  moth,  654 
Webworm,  fall,  485 

garden,  363 
parsnip,  371 
sugar-beet,  301 
Western  cabbage  flea-beetle,  338 

grass-stem  sawfly,  128 
Whale-oil  soap,  46 
Wheat  bulb  worm,  131 
joint-worm,  121 
maggots,  129 
midge,  133 
saw-flies,  127 
saw-fly  borer,  129 
stem  maggot,  129 
straw  worm,  124 
wireworm,  81 
White  arsenic,  43 
White  ants,  655 
White  grubs,  78,  300 
White-lined  sphinx,  232 
Whitefly,  cloudy-winged,  610 
common,  610 
spring-citrus,  633 
woolly,  611 


Whiteflies,  610 

White-headed  scale  fungus,  620 

Window  fly,  640 

Winthemia  4-pustulata,  113 

Wireworms,  80,  300 

Woolly  aphis,  514 

Woolly  whitefly,  611 


INDEX 

Xenopsylla  chaeopsis,  645 


707 


Yellow  aschersonia  fungus,  612 

Yellow  fever,  642 

Yellow  scale,  600 

Yellow-necked  apple  caterpillar,  542 


Wiley  Special  Subject  Catalogues 

For  convenience  a  list  of  the  Wiley  Special  Subject 
Catalogues,  envelope  size,  has  been  printed.  These 
are  arranged  in  groups — each  catalogue  having  a  key 
symbol.  (See  special  Subject  List  Below).  To 
obtain  any  of  these  catalogues,  send  a  postal  using 
the  key  symbols  of  the  Catalogues  desired. 


1 — Agriculture.     Animal  Husbandry.     Dairying.     Industrial 
Canning  and  Preserving. 

2 — Architecture.       Building.       Concrete  and  Masonry. 

3 — Business  Administration  and  Management.     Law. 

Industrial  Processes:    Canning  and  Preserving;     Oil  and  Gas 
Production;   Paint;   Printing;  Sugar  Manufacture;  Textile. 

CHEMISTRY 

4a  General;  Analj'tical,  Qualitative  and  Quantitative;  Inorganic; 

Organic. 
4b  Electro-  and  Physical;  Food  and  Water;   Industrial;  Medical 

and  Pharmaceutical;  Sugar. 

CIVIL  ENGINEERING 

5a  Unclassified  and  Structural  Engineering. 

5b  Materials  and  Mechanics  of  Construction,  including;  Cement 
and  Concrete;  Excavation  and  Earthwork;  Foundations; 
Masonry. 

5c   Railroads;  Surveying. 

5d  Dams;  Hydraulic  Engineering;  Pumping  and  Hydraulics;  Irri- 
gation Engineering;  River  and  Harbor  Engineering;  Water 
Supply. 


CIVIL  ENGINEERING— Cow/inweJ 
5e   Highways;     Municipal     Engineering;     Sanitary     Engineering; 
Water    Supply.      Forestry.      Horticulture,    Botany    and 
Landscape  Gardening. 


6 — Design.  Decoration.  Drawing:  General;  Descriptive 
Geometry;  Kinematics;  IVIechanical. 

ELECTRICAL  ENGINEERING— PHYSICS 

7 — General  and  Unclassified;  Batteries;  Central  Station  Practice; 
Distribution  and  Transmission;  Dynamo-Electro  Machinery; 
Electro-Chemistry  and  Metallurgy;  Measuring  Instruments 
and  Miscellaneous  Apparatus. 


8 — Astronomy.      Meteorology.      Explosives.      Marine    and 
Naval  Engineering.     Military.     Miscellaneous  Books. 

MATHEMATICS 

9 — General;    Algebra;   Analytic  and   Plane   Geometry;    Calculus; 
Trigonometry;  Vector  Analysis. 

MECHANICAL  ENGINEERING 
10a  General  and  Unclassified;  Foundry  Practice;  Shop  Practice. 
10b  Gas  Power  and    Internal   Combustion   Engines;   Heating  and 

Ventilation;  Refrigeration. 
10c   Machine  Design  and  Mechanism;  Power  Transmission;  Steam 

Power  and  Power  Plants;  Thermodynamics  and  Heat  Power. 
11 — Mechanics.  

12— Medicine.  Pharmacy.  Medical  and  Pharmaceutical  Chem- 
istry. Sanitary  Science  and  Engineering.  Bacteriology  and 
Biology. 

MINING  ENGINEERING 

13 — General;  Assaying;  Excavation,  Earthwork,  Tunneling,  Etc.; 
Explosives;  Geology;  Metallurgy;  Mineralogy;  Prospectingj 
Ventilation. 

14 — Food  and  Water.  Sanitation.  Landscape  Gardening. 
Design  and  Decoration.     Housing,  House  Painting. 


